Intervertebral spacer and plate

ABSTRACT

Embodiments herein are generally directed to spinal implants, systems, apparatuses, and components thereof that can be used in spinal fusion and/or stabilization procedures, as well as methods of installation. The spinal implants may include an intervertebral spacer and a plate member.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. patent applicationSer. No. 17/478,213, filed on Sep. 17, 2021, which is a continuation ofU.S. patent application Ser. No. 16/008,088, filed Jun. 14, 2018, whichis a continuation of U.S. patent application Ser. No. 14/802,229, filedJul. 17, 2015, the entire contents of which are hereby incorporate byreference in their entirety for all purposes.

FIELD OF THE INVENTION

The present disclosure relates to intervertebral devices and methodsused to install these devices.

BACKGROUND OF THE INVENTION

Many types of spinal irregularities can cause pain, limit range ofmotion, or injure the nervous system within the spinal column. Theseirregularities can result from, without limitation, trauma, tumor, discdegeneration, and disease. One example of a spinal irregularity that mayresult from disc degeneration is spinal stenosis, the narrowing of aspinal canal, which can result in the compression of spinal nerves suchas the spinal cord or cauda equina. In turn, the nerve compression canresult in pain, numbness, or weakness. Other examples of conditions thatcan result from disc degeneration are osteoarthritis and discherniation.

Often, these irregularities can be treated by performing a discectomyand/or immobilizing a portion of the spine. For example, treatment caninclude a surgical procedure that involves removal and replacement of anaffected intervertebral disc with a prosthesis and the subsequent fusionof adjacent vertebrae. The prosthesis, such as an interbody cage orspacer, may be used either alone or in combination with one or moreadditional devices such as rods, screws, and/or plates.

SUMMARY OF THE INVENTION

Some embodiments herein are directed a vertebral fusion device that caninclude a spacer member comprising a first mating element; and afixation member comprising a first bore extending therethrough and asecond mating element, the second mating element configured toarticulably engage the first mating element.

Other embodiments herein are directed to a vertebral fusion device thatcan include a first endplate comprising a first extension portion, thefirst extension portion comprising a first bore extending therethrough;a second endplate comprising a second extension portion, the secondextension portion comprising a second bore extending therethrough; afirst ramp configured to mate with the first and second endplates; asecond ramp configured to mate with the first and second endplates;wherein the first and second bores each comprise an axis wherein atleast one of the axes intersects a vertical, longitudinal plane of thedevice; and wherein the vertebral fusion device comprises an adjustableheight.

Yet other embodiments herein are directed to a vertebral fusion devicethat can include a first endplate comprising a first extension portion,the first extension portion comprising a first bore extendingtherethrough; a second endplate comprising a second extension portion,the second extension portion comprising a second bore extendingtherethrough; a first ramp configured to mate with the first and secondendplates; a second ramp configured to mate with the first and secondendplates; wherein the first and second bores each comprise an axiswherein at least one of the axes intersects a vertical, longitudinalplane of the device.

Some embodiments herein are directed to a method of installing avertebral fusion device that can include providing a vertebral fusiondevice in a collapsed configuration, comprising: a first endplatecomprising a first extension portion and a second endplate comprising asecond extension portion, both the first and second endplates extendingfrom a first side of the device to a second side of the device; and afirst ramp and a second ramp, both the first ramp and the second rampbeing configured to mate with the first and second endplates, and boththe first ramp and the second ramp extending from the first side of thedevice to the second side of the device, wherein at least one of thefirst and second sides of the device is configured to pivotably expandabout a pivot point; wherein the device defines a first angle withrespect to the pivot point. The method can also include transitioningthe fusion device from the collapsed configuration to an expandedconfiguration, comprising: pivotably expanding at least one of the firstand second sides of the device about the pivot point until the devicedefines a second angle with respect to the pivot point, wherein thesecond angle is greater than the first angle; and inserting a firstfastener into a bore in the first extension portion and inserting asecond fastener into a bore in the second extension portion.

Other embodiments herein are directed to a method of installing avertebral fusion device that can include providing a vertebral fusiondevice in a collapsed configuration, comprising: a first endplatecomprising a first extension portion and a second endplate comprising asecond extension portion, both the first and second endplates extendingfrom a first side of the device to a second side of the device; and afirst ramp and a second ramp, both the first ramp and the second rampbeing configured to mate with the first and second endplates, and boththe first ramp and the second ramp extending from the first side of thedevice to the second side of the device, wherein at least one of thefirst and second sides of the device is configured to pivotably expandabout a pivot point; wherein the device defines a first angle withrespect to the pivot point. The method can also include transitioningthe fusion device from the collapsed configuration to an expandedconfiguration, comprising: pivotably expanding at least one of the firstand second sides of the device about the pivot point until the devicedefines a second angle with respect to the pivot point, wherein thesecond angle is greater than the first angle; and inserting a firstfastener into the first extension portion along a first axis andinserting a second fastener into the second extension portion along asecond axis, wherein at least one of the first and second axes is offsetfrom a vertical, longitudinal plane of the vertebral fusion device.

Still other embodiments herein are directed to a method of installing avertebral fusion device that can include providing a vertebral fusiondevice in a collapsed configuration, comprising: a first endplatecomprising a first extension portion and a second endplate comprising asecond extension portion, both the first and second endplates extendingfrom a first side of the device to a second side of the device; and afirst ramp and a second ramp, both the first ramp and the second rampbeing configured to mate with the first and second endplates, and boththe first ramp and the second ramp extending from the first side of thedevice to the second side of the device, wherein at least one of thefirst and second sides of the device is configured to pivotably expandabout a pivot point; wherein the device defines a first angle withrespect to the pivot point. The method can also include transitioningthe fusion device from the collapsed configuration to an expandedconfiguration, comprising: pivotably expanding at least one of the firstand second sides of the device about the pivot point until the devicedefines a second angle with respect to the pivot point, wherein thesecond angle is greater than the first angle; adjusting a position of atleast one of the first and second extension portions relative to a bodyportion of at least one of the first and second endplates; and insertinga first fastener into the first extension portion along a first axis andinserting a second fastener into the second extension portion along asecond axis, wherein at least one of the first and second axes is offsetfrom a vertical, longitudinal plane of the vertebral fusion device.

Further areas of applicability of the present disclosure will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples, whileindicating certain embodiments, are intended for purposes ofillustration only and are not intended to limit the scope of thedisclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1A illustrates a schematic view of one embodiment of a vertebralfusion device described herein;

FIG. 1B illustrates a schematic view of one embodiment of a vertebralfusion device described herein;

FIGS. 2A-2C illustrate perspective views of one embodiment of avertebral fusion device described herein;

FIG. 2D illustrates a schematic view of one embodiment of a vertebralfusion device described herein;

FIG. 3A illustrates a perspective view of one embodiment of a vertebralfusion device described herein;

FIG. 3B illustrates a schematic view of one embodiment of a vertebralfusion device described herein;

FIG. 4 illustrates a schematic view of one embodiment of a vertebralfusion device described herein;

FIG. 5 illustrates a schematic view of one embodiment of a vertebralfusion device described herein;

FIG. 6 illustrates a schematic view of one embodiment of a vertebralfusion device described herein;

FIG. 7A illustrates a schematic view of one embodiment of a vertebralfusion device described herein;

FIG. 7B illustrates a schematic view of one embodiment of a vertebralfusion device described herein;

FIGS. 8A-8B illustrate schematic views of one embodiment of a vertebralfusion device described herein;

FIG. 9 illustrates a schematic view of one embodiment of a vertebralfusion device described herein;

FIGS. 10A-10B illustrate schematic views of one embodiment of avertebral fusion device described herein;

FIGS. 11A-11B illustrate schematic views of one embodiment of avertebral fusion device described herein;

FIGS. 12A-12B illustrate exploded views of one embodiment of a vertebralfusion device described herein;

FIGS. 12C-12D illustrate perspective views of one embodiment of avertebral fusion device described herein;

FIG. 12E illustrates a cross-sectional view of one embodiment of avertebral fusion device described herein;

FIG. 12F illustrates a perspective view of one embodiment of a vertebralfusion device described herein;

FIG. 13A illustrates an exploded view of one embodiment of a vertebralfusion device described herein; and

FIGS. 13B-13E illustrate perspective views of one embodiment of avertebral fusion device described herein.

DETAILED DESCRIPTION

In a spinal fusion procedure, affected tissue between adjacent vertebraemay be removed and replaced with a prosthesis, such as an interbodycage, spacer, or other spinal implant. A plate and/or screws may also beused to secure the prosthesis within the intervertebral disc space. Theintervertebral disc space can be accessed via various approaches (e.g.,anterior, posterior, transforaminal, and/or lateral). In a lateralprocedure, the prosthesis may be inserted through an incision on apatient's side; advantageously, this type of approach may generallyavoid muscles and nerves that may otherwise be encountered in ananterior, posterior, and/or transforaminal approach. However, a lateralapproach may be difficult in a patient's lumbar spine (e.g., between theL4 and L5 vertebrae), as the patient's bones, nerves, and/ormusculature, such as the iliac crest, lumbar plexus, and/or psoas, caninhibit the trajectory of the screws. Accordingly, disclosed herein arevertebral fusion devices that can include an interbody spacer and aplate configured for use in lateral lumbar interbody fusion (LLIF)procedures, and that can enable implant and screw placement even in thevicinity of the iliac crest and other anatomy.

Some embodiments herein may be directed to vertebral fusion devices thatcan be configured for insertion between adjacent vertebrae via a lateralprocedure (e.g., lateral lumbar interbody fusion). For example, thedevice may have a length (e.g., as measured between a leading end and atrailing end) that is about 100-300% greater than a width thereof (e.g.,as measured in the anterior-posterior direction). The device may alsohave a length that is configured to laterally span a vertebral endplate.For example, the device may have a length in the range of from about 35mm to about 65 mm. The device may also have a width in the range of fromabout 15 mm to about 30 mm. Some embodiments herein may be directed toexpandable vertebral fusion devices that can be configured for use inlateral procedures. The expandable vertebral fusion devices describedherein may have a variable height and may be configured to collapse to asmaller height prior to insertion and/or expand to a larger height afterinsertion. In some embodiments, the expanded height can be from about25% to about 200% greater than the collapsed height. In otherembodiments, the expanded height can be from about 100% to about 150%greater than the collapsed height. In some embodiments, the collapsedheight can be in the range of from about 5 mm to about 10 mm, and/or theexpanded height can be in the range of from about 15 mm to about 20 mm.In some embodiments, the expandable vertebral fusion devices may alsohave a variable lordotic angle. These devices may include one or moremembers configured to pivot about a pivot point. These devices may beconfigured to collapse to a smaller angle (e.g., 10.4°) prior toinsertion and/or expand to a larger angle (e.g., 22.5°) after insertion.Accordingly, these devices may be configured for use inminimally-invasive surgery (MIS). For example, they may be insertedthrough a relatively small incision and/or through a cannula, therebyreducing trauma to the patient. Conversely, the expandable vertebralfusion devices described herein may be configured to expand to a widthgreater than that of other implants in the art, without requiring alarger incision. Furthermore, the height and/or lordotic angle of theexpandable vertebral fusion devices may be adjusted after insertion,thereby providing a customized fit within the intervertebral space.

Components of all of the devices and systems disclosed herein can bemade of materials known to those skilled in the art, including metals(e.g., titanium), metal alloys (e.g., stainless steel, titanium alloys,and/or cobalt-chromium alloys), ceramics, polymers (e.g., poly etherketone (PEEK), polyphenylene sulfone (PPSU), polysulfone (PSU),polycarbonate (PC), polyetherimide (PEI), polypropylene (PP),polyacetals, or mixtures or co-polymers thereof), allograft, and/orcombinations thereof. For example, a spacer member as described hereinmay include a polymeric material and a fixation member as describedherein may include a metallic material. In some embodiments, the systemsand devices may include radiolucent and/or radiopaque materials. Inother embodiments, one or more components may be coated with a bonegrowth-enhancing material, such as hydroxyapatite. The components canalso be machined and/or manufactured using techniques known to thoseskilled in the art. For example, polymeric components may beinjection-molded or blow-molded. Additionally, the devices disclosedherein may be used together with materials that encourage bone growth,such as bone graft material, demineralized bone matrix, bone chips,and/or bone morphogenetic proteins. In some embodiments, these materialsmay advantageously be packed into hollow areas of the devices describedherein.

As described herein, the spinal implants of the present disclosure maybe configured for placement between two adjacent vertebrae, for example,as part of a spinal fusion procedure. These spinal implants may bereferred to as, without limitation, interbody spacers, interbody fusiondevices, vertebral fusion devices, interbody cages, and/orintervertebral cages. Each of the spinal implants described herein mayinclude superior and/or inferior surfaces that are configured to engageand/or contact a vertebral endplate or other vertebral surface. In someembodiments, the superior and/or inferior surfaces may be convex,corresponding to the topography of the endplates. Additionally, thesuperior and/or inferior surfaces of each of the spinal implantsdescribed herein may include one or more texturizing members. Examplesof such texturizing members include, but are not limited to,projections, bumps, teeth, grooves, peaks, spikes, and/or knurling.These texturizing features may advantageously enhance the interaction orfiction, and/or reduce movement, between the implant and the vertebrae.The spinal implants of the present disclosure may be configured forinsertion between adjacent vertebrae. In some embodiments, the spinalimplants described herein may be configured for insertion between lumbarvertebrae (e.g., between L4-L5 vertebrae). The spinal implants describedherein may be configured for insertion using a minimally-invasiveprocedure (e.g., through a cannula). The spinal implants describedherein may be configured for insertion using a variety of approaches. Insome embodiments, the spinal implants may be configured for lateralinsertion. In other embodiments, the spinal implants of the presentdisclosure may be configured for anterior, posterior, and/ortransforaminal insertion. Those skilled in the art may appreciate thatdirectional terms such as “anterior,” “posterior,” “superior,”“inferior,” “top,” and “bottom,” and the like may be used herein fordescriptive purposes and do not limit the orientation(s) in which thedevices may be used. For example, those skilled in the art mayappreciate that, in use, a “superior” surface may be installed adjacentan inferior vertebra, and vice versa. Accordingly, a feature describedas being on top may actually be oriented towards the bottom afterinstallation.

Some embodiments disclosed herein are directed to a vertebral fusiondevice that can include a spacer member and a fixation member (e.g.,plate). The spacer member and the fixation member can be separate, orthey can be integrated. In some embodiments, the device can include twoor more fixation members and/or a multi-piece fixation member. In someembodiments, the fixation member(s) may be configured to move relativeto the spacer member along one or more paths. The fixation member caninclude a bore configured to receive a fastener (e.g., bone screw,anchor, and/or staple) therethrough. These embodiments canadvantageously direct the trajectory of a fastener, and/or can enable auser to alter the trajectory of a fastener, so as to avoid anatomicalstructures such as the lumbar plexus, psoas major, and/or iliac crest.In some embodiments, the spacer member can be expandable. For example,the spacer member can include a variable height and/or a variablelordotic angle.

Turning now to FIGS. 1A-B, some embodiments herein are directed to avertebral fusion device that can include a spacer member and a fixationmember. With respect to FIG. 1A, vertebral fusion device 10 can includea spacer member 2 and a fixation member 4, wherein the fixation member 4may be configured to be offset from a vertical, longitudinal plane 6 ofthe spacer member 2. The spacer member 2 may be configured for insertionbetween adjacent vertebrae via a lateral procedure (e.g., lateral lumbarinterbody fusion). For example, the spacer member 2 may have a length(e.g., as measured between a leading end 14 and a trailing end 16) thatis about 100-300% greater than a width thereof (e.g., as measured in theanterior-posterior direction). The spacer member 2 may also have alength that is configured to laterally span a vertebral endplate. Forexample, the spacer member 2 may have a length in the range of fromabout 40 mm to about 60 mm. The fixation member 4 may include at leastone bore 8 configured to receive a fastener 12 therethrough. Thefastener 12 may be, for example, a bone screw, anchor, staple, or spike.In some embodiments, the fixation member 4 may include two, three, four,or more bores configured to receive a fastener therethrough. In someembodiments, at least two bores may be horizontally and/or verticallydisplaced from each other. The fixation member 4 may have a height thatis greater than a height of the spacer member 2. For example, thefixation member 4 may have a height that is greater than a distancebetween two adjacent vertebrae. In some embodiments that include twobores, the two bores may be spaced apart by a distance that is greaterthan a distance between two adjacent vertebrae. The fixation member 4may be configured to be offset (e.g., anteriorly) from the vertical,longitudinal plane 6 by an angle α, for example, in the range of fromabout 5° to about 90°. In some embodiments, α may be in the range offrom about 5° to about 45°. In other embodiments, α may be in the rangeof from about 20° to about 30°.

Other embodiments herein are directed to methods of installing thevertebral fusion device 10. In these embodiments, the spacer member 2may be inserted along a first trajectory (e.g., laterally). The firsttrajectory may be along and/or parallel to the vertical, longitudinalplane 6. The fixation member 4 may be inserted along a second trajectorythat intersects the first trajectory (e.g., obliquely and/oranterolaterally). The first and second trajectories may intersect toform the angle α, for example, in the range of from about 5° to about90°. Fastener 12 may be inserted into bore 8 along a third trajectorythat intersects the first trajectory (e.g., obliquely and/oranterolaterally). In some embodiments, the third trajectory may beparallel to the second trajectory.

An alternative embodiment is illustrated in FIG. 1B. As illustratedtherein, vertebral fusion device 30 may include some or all of thefeatures of vertebral fusion device 10, unless expressly describedotherwise. Additionally, vertebral fusion device 30 may include asecuring member 32. The securing member 32 may include a head 34 and anelongate body 36. The head 34 may be configured to engage a tool such asan inserter and/or a driver. The elongate body 36 may include anengagement feature such as threading or ratcheting. For example, in someembodiments the securing member 32 may be a screw. The securing member32 may be configured to couple the spacer member 2 and/or the fixationmember 4. For example, the elongate body 36 may be configured to engagea threaded opening 31 in the fixation member 4 and/or a threaded opening33 in the spacer member 2. In use, after the spacer member 2, thefixation member 4, and/or the fastener 12 are inserted, the fixationmember 4 may be coupled with the spacer member 2. In some embodiments,this step can include coupling the securing member 32 with the fixationmember 4 and the spacer member 2, for example, by threading the securingmember 32 therein. The securing member 32 may also be inserted along atrajectory (e.g., a fourth trajectory) that is offset from the vertical,longitudinal plane 6. The fourth trajectory may be parallel to thesecond and/or third trajectories, as described herein with respect tovertebral fusion device 10.

Some embodiments herein are directed to a vertebral fusion device thatcan include a spacer member and a fixation member, wherein the fixationmember is configured to move relative to the spacer member when it iscoupled thereto. Turning to FIGS. 2A-C, some embodiments herein aredirected to a vertebral fusion device 50 that can include a spacermember 52 and a fixation member 54. As illustrated in FIG. 2B, thespacer 52 can include a first (e.g., leading) end 56, a second (e.g.,trailing) end 58, a first (e.g., anterior) side 66, and a second (e.g.,posterior) side 68. The spacer member 52 may include an upper (e.g.,superior) surface 60, a lower (e.g., inferior) surface (not shown), andan outer side surface 62 along an outer perimeter thereof. The spacermember 52 may be generally rectangular. In some embodiments, the outerside surface 62 can include at least one curved portion 70, asillustrated, for example, in FIG. 2C. The curved portion 70 may appearcurved (e.g., concave) when viewed from the upper surface 60 and/or thelower surface. The curved portion 70 may be located at the trailing end58 and/or anterior side 66 of the spacer member 52. As illustrated inFIGS. 2A-C, the curved portion may extend at least partially along thetrailing end 58 and/or anterior side 66. As illustrated in FIGS. 2A-B,the spacer member 52 can include a central cavity 64. In someembodiments, the central cavity 64 may be configured to receive bonegrowth material therein. The spacer member 52 may be configured forinsertion between adjacent vertebrae via a lateral procedure (e.g.,lateral lumbar interbody fusion). For example, the spacer member 52 mayhave a length (e.g., as measured between the leading end 56 and thetrailing end 58) that is about 100-300% greater than a width thereof(e.g., as measured in the anterior-posterior direction). The spacermember 52 may also have a length that is configured to laterally span avertebral endplate. For example, the spacer member 52 may have a lengthin the range of from about 40 mm to about 60 mm.

In some embodiments, the spacer member 52 can include a first matingelement 72, as illustrated in FIG. 2B. As illustrated in FIG. 2B, thefirst mating element 72 can include a groove, slot, notch, channel,and/or recess. In some embodiments, the groove, slot, notch, channel,and/or recess may include a tapered cross-section. In other embodiments,it may include a T-shaped cross-section, and may be referred to as aT-slot. In yet other embodiments, the first mating element 72 caninclude a protrusion, projection, lip, and/or overhang. The protrusionand/or projection can also include a tapered cross-section. The firstmating element 72 can extend along a curved path. The first matingelement may be disposed on the curved portion 70 of the outer sidesurface 62. In some embodiments, the first mating element 72 may bedisposed on at least a portion of the trailing end 58 and at least aportion of the anterior side 66.

The fixation member 54 can include a second mating element 74. Asillustrated in FIG. 2C, the second mating element 74 can be disposed ona coupling portion 80 of the fixation member. The coupling portion 80may be configured to be at least partially disposed between the upperand lower surfaces of the spacer member 52. The coupling portion 80 maybe generally perpendicular to a fixation portion 82 of the fixationmember 54. In some embodiments, the second mating element 74 can includea groove, slot, notch, channel, and/or recess. The groove, slot, notch,channel, and/or recess may include a tapered cross-section. In otherembodiments, it may include a T-shaped cross-section, and may bereferred to as a T-slot. In yet other embodiments, the second matingelement 74 can include a protrusion, projection, lip, and/or overhang.The protrusion and/or projection can also include a taperedcross-section. The first and/or second mating elements 72, 74 may eachextend along a curved path. In some embodiments, the first and secondmating elements 72, 74 may include the same radius of curvature.

In some embodiments, the first mating element 72 can include a grooveand the second mating element 74 can include a protrusion, or viceversa. Those skilled in the art may appreciate that when the first andsecond mating elements 72, 74 are engaged, they may form a joint (e.g.,a dovetail joint, a tongue and groove joint, and/or a splice joint).Accordingly, the fixation member 54 may be configured to jointedlycouple to the spacer member 52. The second mating element 74 may beconfigured to articulably, pivotably, and/or slideably engage the firstmating element 72. The second mating element 74 may be disposed on aleading side of the fixation member 54. For example, the fixation member54 may be configured to articulate at least partially about the spacermember 52 by translating the second mating element 74 along the firstmating element 72.

The fixation member 54 may include at least one bore 76, as illustratedin FIG. 2A. The bore 76 may be disposed on the fixation portion 82 ofthe fixation member 54. The bore 76 may be configured to receive afastener therethrough. The fastener may be, for example, a bone screw,anchor, staple, or spike. In some embodiments, the fixation member 54may include two, three, four, or more bores configured to receive afastener therethrough. In some embodiments, at least two bores may behorizontally and/or vertically offset from each other. As illustrated inFIG. 2A, the fastener member 54 can include two bores 76 that arehorizontally and vertically offset from each other. The fixation member54 may be configured to extend beyond the upper surface 60 and/or thelower surface of the spacer member 52. In some embodiments, at least onebore 76 may be located above the upper surface 60 of the spacer member52 when the spacer member 52 and the fixation member 54 are articulablycoupled. The fixation member 54 may have a height that is greater than aheight of the spacer member 52 (e.g., as measured between the uppersurface 60 and the lower surface). For example, the fixation member 4may have a height that is greater than a distance between two adjacentvertebrae. In some embodiments that include two bores, the two bores maybe spaced apart by a distance that is greater than a distance betweentwo adjacent vertebrae. The fixation member 54 can also include areceptacle 78 therethrough. The receptacle 78 can include a threadedinterior. In some embodiments, the receptacle 78 can be configured tothreadably receive an inserter or implant holder therein. The fixationportion 82 of the fixation member 54 can also include one or morenotches 84, as illustrated in FIG. 2A. The notches 84 may each beconfigured to engage a protrusion, such as a tab, on the inserter. Inuse, the protrusion may key into the notch 84 and/or the spacer member52, advantageously inhibiting motion of the fixation member 54 duringinsertion.

In some embodiments, the vertebral fusion device 50 can also include alocking member (not shown). The locking member can be configured toreversibly engage the spacer member 52 and/or the fixation member 54. Insome embodiments, the locking member can include a clamp, clasp, and/orcatch. The locking member can be configured to inhibit movement of thefixation member 54 relative to the spacer member 52 when in a lockedconfiguration. When in an unlocked configuration, the locking member canallow movement of the fixation member 54 relative to the spacer member52. The vertebral fusion device 50 can reversibly transition between thelocked and unlocked configuration.

Also described herein are methods for installing the vertebral fusiondevice 50. These methods can include providing the vertebral fusiondevice 50, wherein the spacer member 52 and the fixation member 54 arearticulably, pivotably, and/or slideably engaged (e.g., the first andsecond mating elements 72, 74 may be articulably, pivotably, and/orslideably engaged). In embodiments that include a locking member, thevertebral fusion device 50 may be provided in the locked configurationas described herein. In some embodiments, the vertebral fusion device 50may be provided (e.g., inserted) between two adjacent vertebrae (e.g.,between the L4 and L5 vertebrae), for example, along a lateral approach.In some embodiments, an inserter may be coupled to the vertebral fusiondevice 50 during the insertion process, for example, by threadablyengaging the receptacle 78 and/or keying into the notches 84. In someembodiments, the inserter may be coupled to both the fixation member 54and the spacer member 52. Advantageously, the inserter may inhibitmovement of the fixation member 54 during insertion and/or placement. Inembodiments that include a locking member, the device 50 may then beunlocked, e.g., by releasing the locking member. A position (e.g.,orientation) of the fixation member 54 (e.g., the position of bore 76)may then be adjusted relative to the spacer member 52. The position ofthe fixation member 54 may be adjusted, for example, by articulating,pivoting, and/or sliding the fixation member 54 along the path definedby the first mating element 72. The method can also include inserting afirst fastener member into the bore 76. In some embodiments, the firstfastener member may be inserted along an anterolateral trajectory. Inother embodiments, the first fastener member may be inserted along anupwards trajectory (e.g., towards a superior vertebra). In use, thoseskilled in the art may appreciate that the vertebral fusion device 50may advantageously enable a user to adjust the position of the bore 76,thereby adjusting fastener placement. Accordingly, a user may be able toposition the bore 76 to avoid certain anatomical structures such as thepsoas major, lumbar plexus, and/or iliac crest.

An alternative embodiment, vertebral fusion device 100, is illustratedin FIG. 2D. Unless expressly described otherwise, vertebral fusiondevice 100 may include some or all of the features of vertebral fusiondevice 50. For example, vertebral fusion device 100 may include a spacermember 114 which includes some or all of the same features as spacermember 52. Vertebral fusion device 100 can include a modified fixationmember 102. The fixation member 102 can include a threaded post 104, acoupling portion 106, and a fixation portion 108. The fixation portion108 can include one or more bores (not shown) as described with respectto fixation member 54. The coupling portion 106 can include some or allof the features of coupling portion 80 (e.g., a mating element asdescribed herein). The threaded post 104 can extend, e.g., proximally,from the coupling portion 106. The fixation portion 108 can include athrough-hole 110 configured to receive at least a portion of thethreaded post 104 therethrough. The through-hole 110 may include asmooth (e.g., non-threaded) interior surface. The fixation portion 108may be coupled to an actuator 112. The actuator 112 may include athreaded hole configured to mate with the threaded post 104. Theactuator 112 can also include an exterior tool-engaging surface. In someembodiments, the actuator 112 can include a nut. In use, the fixationportion 108 may be configured to translate along an axis defined by thethreaded post 104, towards and/or away from the spacer member 114.

Also described herein are methods for installing the vertebral fusiondevice 100. These methods can be the same or similar to those describedwith respect to the vertebral fusion device 50. Additionally, the stepof adjusting a position (e.g., orientation) of the fixation member 102can include adjusting (e.g., increasing and/or reducing) a distancebetween the spacer member 114 and the fixation member 102. The distancecan be measured horizontally. The step of adjusting the fixation member102 can include engaging the actuator 112. In embodiments where theactuator 112 includes a nut, this step can include threading orunthreading the nut along the threaded post 104. As the nut travelsalong the threaded post 104, it may advantageously also causetranslational motion of the fixation member 102 in the same direction(e.g., proximally and/or distally). Advantageously, the ability toadjust the position of the fixation member 102 (e.g., the bore(s)) bytranslation and articulation can provide increased freedom to a userwith regards to fastener placement.

Other embodiments herein are directed to a vertebral fusion device thatcan include a movable (e.g., articulable and/or translatable) fixationmember as described herein and that can also include an expandablespacer member. The expandable spacer member can include a variableheight (e.g., as measured between an upper surface and a lower surface).The expandable spacer member may be generally rectangular, and in someembodiments may be configured for lateral insertion as described herein.Turning to FIGS. 3A-B, vertebral fusion device 150 can includeexpandable spacer member 152. The expandable spacer member 152 caninclude a first (e.g., upper) endplate 156, a second (e.g., lower)endplate 158, a frame 160, an articulating screw support 162, a link164, and a nut 166. The expandable spacer member 152 may also include adrive link (not shown). The drive link may be configured to engage thefirst and second endplates 156, 158 and may be configured to pull and/ordisplace the endplates 156, 158 relative to the frame 160. Theexpandable spacer member 152 may also include a first (e.g., distaland/or leading) end 170 and a second (e.g., proximal and/or trailing)end 172. In some embodiments, vertebral fusion device 150 may includeone or more features of the devices described in U.S. Patent PublicationNo. 2014/0249628, entitled “ARTICULATING EXPANDABLE INTERVERTEBRALIMPLANT,” published on Sep. 4, 2014, which is hereby incorporated byreference herein in its entirety for all purposes.

The frame 160 can include one or more lift ramps 168 on the upper and/orlower surfaces thereof. Each lift ramp 168 may have a surface that isinclined from an intermediate portion of the frame 160 towards theproximal end 172. Each lift ramp 168 may be configured to slideablyengage an expansion ramp 174 on the first and/or second endplates 156,158. Each expansion ramp 174 may have a surface that is inclined from anintermediate portion of the first and/or second endplates 156, 158towards the distal end 170. In use, the spacer member 152 may beexpanded by translating the frame 160 relative to the first and secondendplates 156, 158. The lift ramps 168 may engage the expansion ramps174 and urge the first and second endplates 156, 158 apart, therebyincreasing the height of the spacer member 152.

The nut 166 can include internal threads that may be configured to matewith external threads of the link 164. The nut 166 can also include oneor more tool-engaging portions 176 disposed on an outer surface thereof.The nut 166 may be rotatably retained along a fixed axial orientationwithin the articulating screw support 162. In use, a tool (e.g., adriver) may engage and rotate the nut 166. As the nut 166 rotates, link164 may be advanced or withdrawn with respect to the frame 160, therebymoving endplates 156, 158 with respect to the frame 160 and causing anexpansion or contraction of the height of the expandable spacer member152.

The articulating screw support 162 may be movably (e.g., slideably,articulably, and/or pivotably) coupled to the frame 160. The frame 160can also include a first mating element 178. The first mating element178 can include a groove, slot, notch, channel, and/or recess. In someembodiments, the groove, slot, notch, channel, and/or recess may includea tapered cross-section. In other embodiments, it may include a T-shapedcross-section, and may be referred to as a T-slot. In yet otherembodiments, the first mating element 178 can include a protrusion,projection, lip, and/or overhang. The protrusion and/or projection canalso include a tapered cross-section. The first mating element 178 maybe disposed on a curved portion of the trailing end 172. In someembodiments, the first mating element 178 may be disposed on at least aportion of the trailing end 172 and/or at least a portion of an anteriorside.

The articulating screw support 162 can include a second mating element180. The second mating element 180 may be disposed on an inner surfaceof the articulating screw support 162. In some embodiments, the secondmating element 180 can include a groove, slot, notch, channel, and/orrecess. The groove, slot, notch, channel, and/or recess may include atapered cross-section. In other embodiments, it may include a T-shapedcross-section, and may be referred to as a T-slot. In yet otherembodiments, the second mating element 180 can include a protrusion,projection, lip, and/or overhang. The protrusion and/or projection canalso include a tapered cross-section. The first and/or second matingelements 178, 180 may each extend along a curved path. In someembodiments, the first and second mating elements 178, 180 may includethe same radius of curvature.

In some embodiments, the first mating element 178 can include a grooveand the second mating element 180 can include a protrusion, or viceversa. Those skilled in the art may appreciate that when the first andsecond mating elements 178, 180 are engaged, they may form a joint(e.g., a dovetail joint, a tongue and groove joint, and/or a splicejoint). Accordingly, the articulating screw support 162 may beconfigured to jointedly couple to the expandable spacer member 152. Thesecond mating element 180 may be configured to articulably, pivotably,and/or slideably engage the first mating element 178. For example, thearticulating screw support 162 may be configured to articulate at leastpartially about the expandable spacer member 152 by translating thesecond mating element 180 along the first mating element 178.

In some embodiments, the articulating screw support 162 can beconfigured to engage a fixation member, such as fixation member 154,illustrated in FIG. 3B, or any other fixation members described herein.The fixation member 154 can be directly or indirectly attached, mounted,and/or coupled to the articulating screw support 162. In someembodiments, the fixation member 154 can be mechanically coupled to thearticulating screw support 162. In use, the nut 166 can be movable,thereby enabling expansion and/or contraction of the expandable spacermember 152 from a variety of approaches. Additionally, the fixationmember can also be movable, thereby enabling a user to position thefixation member in an orientation that avoids certain anatomicalstructures as described herein.

As illustrated in FIG. 3B, in some embodiments, the fixation member 154can be indirectly engaged with the articulating screw support 162. Thevertebral fusion device 150 can include a threaded post 182. In someembodiments, the threaded post 182 may be an axial extension of link 164(e.g., the threaded post 182 may extend lengthwise along axis 186). Thefixation member 154 can include some or all of the features of fixationmember 102. For example, fixation member 154 can include a through-hole184 configured to receive at least a portion of the threaded post 182therethrough. The through-hole 184 may include a smooth (e.g.,non-threaded) interior surface. The vertebral fusion device 150 may alsoinclude an actuator 188. The actuator 188 may include a threaded holeconfigured to mate with the threaded post 182. The actuator 188 may alsoinclude an exterior tool-engaging surface. In some embodiments, theactuator 188 can include a nut. In use, the fixation member 154 mayadvantageously be configured to translate along the axis 186, towardsand/or away from the expandable spacer member 152.

Also described herein are methods for installing the vertebral fusiondevice 150. These methods can include providing the vertebral fusiondevice 150 in a collapsed configuration, wherein the device 150 has afirst height (e.g., as measured from an upper surface of endplate 156 toa lower surface of endplate 158). In some embodiments, this step caninclude inserting the vertebral fusion device between two adjacentvertebrae (e.g., between the L4 and L5 vertebrae), for example, along alateral, oblique, or anterolateral approach. These methods can alsoinclude adjusting a position (e.g., orientation) of the link 164 and/orthe fixation member 154 relative to the expandable spacer member 152.The position of the link 164 and/or fixation member 154 can be adjusted,for example, by articulating, pivoting, and/or sliding the articulatingscrew support 162 along the path defined by the first mating element178. These methods can also include expanding the vertebral fusiondevice 150 to an expanded configuration, wherein the device 150 has asecond height that is greater than the first height. This step caninclude rotating the nut 166, thereby applying a force to the frame 160and separating the endplates 156, 158 as described herein. In someembodiments, this step can also include inserting a tool (e.g., adriver) which engages and rotates the nut 166. The tool can be insertedalong a lateral, oblique, or anterolateral approach. Advantageously, acurved path of the first mating element 178 can enable actuation of nut166 at an angle with respect to a longitudinal axis of spacer 152. Inthis manner, spacer member 152 may be inserted into the body along anon-linear path, for example during a transforaminal, posterior, and/orlateral insertion, and articulating screw support 162 may be positionedto be more readily accessible along the insertion path (e.g., obliqueand/or anteriolateral) to a tool end which engages nut 166 for rotation,thereby minimizing disturbance of body tissue. In some embodiments, thedevice 150 can be inserted along a lateral path and the tool can beinserted along an oblique and/or anteriolateral path. In otherembodiments, the device 150 can be inserted along an oblique and/oranteriolateral path and articulated into a lateral position (e.g., theexpandable spacer member 152 can articulate relative to the link 164and/or fixation member 154).

The method can also include inserting a first fastener member into abore on the fixation member 154. In some embodiments, the first fastenermember may be inserted along an anterolateral and/or oblique trajectory.In other embodiments, the first fastener member may be inserted along anupwards trajectory (e.g., towards a superior vertebra). In use, thoseskilled in the art may appreciate that the vertebral fusion device 150may advantageously enable a user to adjust the position of the bore,thereby adjusting fastener placement. Accordingly, a user may be able toposition the bore to avoid certain anatomical structures such as thepsoas major, lumbar plexus, and/or iliac crest.

In some embodiments, for example, those relating to the vertebral fusiondevice illustrated in FIG. 3B, the step of adjusting a position (e.g.,orientation) of the fixation member 154 can include adjusting (e.g.,increasing and/or reducing) a distance between the spacer member 152 andthe fixation member 154. The distance can be measured along axis 186.The step of adjusting the fixation member 154 can include engaging theactuator 188. In embodiments where the actuator 188 includes a nut, thisstep can include threading or unthreading the nut along the threadedpost 182. As the nut travels along the threaded post 182, it mayadvantageously also cause translational motion of the fixation member154 in the same direction (e.g., proximally and/or distally).Advantageously, the ability to adjust the position of the fixationmember 154 (e.g., the bore(s)) by translation and articulation canprovide increased freedom to a user with regards to fastener placement.

Turning to FIG. 4 , some embodiments herein are directed to a vertebralfusion device 200 that can include a spacer member 202 and a firstmovable fixation member 204. The first movable fixation member 204 canbe configured to be moveably (e.g., articulably, pivotably, and/orslideably) coupled and/or engaged to the spacer member 204, as describedherein with respect to, e.g., vertebral fusion devices 50, 100, and/or150. For example, the first movable fixation member 204 can include asecond mating element configured to engage a corresponding first matingelement on the spacer member 202. In some embodiments, the first movablefixation member 204 can be configured to translate towards and/or awayfrom the spacer member 202, for example, as described herein withrespect to vertebral fusion device 100. The first movable fixationmember 204 can include a height that, when coupled to the spacer member202, extends from a central portion 206 of the spacer member to aposition above and/or beyond an upper or lower surface 208, 210 of thespacer member 202. As illustrated in FIG. 4 , the height of the firstmovable fixation member 204 can extend beyond/above the upper surface208 of the spacer member 202. In these embodiments, the first movablefixation member 204 may be referred to as an upper fixation member. Inother embodiments, the height of the first movable fixation member 204can extend beyond/below the lower surface 210 of the spacer member. Inthese embodiments, the first movable fixation member 204 may be referredto as a lower fixation member.

As illustrated in FIG. 4 , in some embodiments, the first movablefixation member 204 can include a single bore 212. The bore 212 can beconfigured to receive a fastener (e.g., a bone screw, anchor, and/orstaple) therethrough. In other embodiments, the first movable fixationmember 204 can include two or more bores. The two or more bores may behorizontally displaced relative to each other (e.g., displaced along awidth of the fixation member 204). In some embodiments, the two or morebores may be vertically aligned (e.g., aligned along the height of thefixation member 204).

As illustrated in FIG. 4 , the vertebral fusion device 200 can include asecond fixation member 214. The second fixation member 214 may bemovable or stationary. In embodiments where the second fixation member214 is movable, it may include some or all of the same features as firstfixation member 204. In these embodiments, the spacer member 202 mayinclude an additional mating element (e.g., curved tongue or groove)configured to engage a corresponding mating element on the secondfixation member 214. In embodiments where the second fixation member 214is stationary, it may be coupled (e.g., attached) to the spacer member202. In some embodiments, the second fixation member 214 and the spacermember 202 can together make up a unitary body. The second fixationmember 214 can include a height that, when coupled to the spacer member202, extends from the central portion 206 of the spacer member 202 to aposition above and/or beyond an upper or lower surface 208, 210 of thespacer member 202. As illustrated in FIG. 4 , the height of the secondfixation member 214 can extend beyond/below the lower surface 210 of thespacer member 202. In these embodiments, the second fixation member maybe referred to as the lower fixation member. In other embodiments, theheight of the second fixation member 214 can extend beyond/above theupper surface 208 of the spacer member 202. In these embodiments, thesecond fixation member may be referred to as the upper fixation member.As illustrated in FIG. 4 , the second fixation member 214 may extendaway from the spacer member 202 in a direction opposite that of thefirst fixation member 204.

Embodiments herein are also directed to methods of installing thevertebral fusion device 200. These methods can include some or all ofthe steps described herein with respect to vertebral fusion devices 50,100, and 150, for example. These methods can include providing thevertebral fusion device 200, wherein the spacer member 202 and thefixation member 204 are articulably, pivotably, and/or slideably engaged(e.g., the first and second mating elements (not shown) may bearticulably, pivotably, and/or slideably engaged). In embodiments thatinclude a locking member, the vertebral fusion device 200 may beprovided in a locked configuration. The locking member may inhibitmovement of the movable fixation member(s). In some embodiments, thevertebral fusion device 200 may be provided (e.g., inserted) between twoadjacent vertebrae (e.g., between the L4 and L5 vertebrae), for example,along a lateral approach. In embodiments that include a locking member,the device 200 may then be unlocked, e.g., by releasing the lockingmember. A position (e.g., orientation) of the first movable fixationmember 204 (e.g., the position of bore 212) may then be adjustedrelative to the spacer member 202. The position of the first movablefixation member 204 may be adjusted, for example, by articulating,pivoting, and/or sliding the fixation member 204 along the path definedby the first mating element. In some embodiments, this step can alsoinclude axially translating the fixation member 204 towards and/or awayfrom the spacer member 202. The method can also include inserting afirst fastener member into the bore 212. In some embodiments, the firstfastener member may be inserted along an anterolateral trajectory. Inother embodiments, the first fastener member may be inserted along anupwards trajectory (e.g., towards a superior vertebra).

In embodiments where the second fixation member 214 is stationary, asecond fastener member can be inserted into bore 216 either before orafter the first fastener member is inserted into bore 212.Advantageously, the second fixation member 214, when stationary, canprovide stability to the device 200 while the first fixation member 204can provide adjustable fastener placement. In embodiments where thesecond fixation member 214 is movable, methods herein can also includethe steps of adjusting a position (e.g., orientation) of the secondfixation member 214 relative to the spacer member 202 and inserting afastener member into a bore thereof. In these embodiments, the first andsecond fixation members 204, 214 may advantageously be independentlyadjustable. Accordingly, each of the first and second fixation members204, 214 may be positioned differently to accommodate the particularanatomical features of a patient and/or the planned trajectory of theassociated fastener (e.g., towards the inferior vertebra or towards thesuperior vertebra).

Other embodiments herein are directed to vertebral fusion devices thatcan include a spacer member and a fixation member, wherein the fixationmember is configured to translate (e.g., telescope, extend, and/orretract) relative to the spacer member. In some embodiments, thefixation member may be configured to translate along a horizontal axis.In other embodiments, the fixation member may be configured to translatealong a vertical axis. In yet other embodiments, the fixation member maybe configured to translate along an axis that defines an angle in therange of from about 0° to about 180° relative to a side surface of thespacer member.

As illustrated in FIG. 5 , vertebral fusion device 250 can include aspacer member 252 and a fixation member 254, wherein the fixation member254 can be translatably coupled to and/or engaged with the spacer member252. The spacer member 252 can include a first (e.g, distal and/orleading) side 256, a second (e.g., proximal and/or trailing) side 258, athird (e.g., anterior) side 260, and/or a fourth (e.g., posterior) side262. The four sides can define a generally rectangular shape. The spacermember 252 can include a vertical, longitudinal plane 274. The spacermember 252 can also include a cavity 264. The cavity 264 can include anopening 266 on the third side 260 of the spacer member 252. The spacermember 252 can also include a first mating element (not shown). Thefirst mating element of the spacer member 252 can be configured toengage the second mating element 268 of the fixation member 254,described herein. In some embodiments, the spacer member 252 can includetwo or more first mating elements. The first mating element may bedisposed within the cavity 264. The first mating element can include,for example, a ramp, rack, and/or track. In some embodiments, the firstmating element can define a curved, angled, and/or straight path. Thepath may extend generally transversely towards and/or away from theopening 266. In some embodiments, the path may be parallel to ahorizontal plane of the spacer member 252. In other embodiments, thepath may be perpendicular or skewed to the horizontal plane.

The fixation member 254 can include a second mating element 268. Thefixation member 254 can include two or more second mating elements 268.The second mating element 268 may be configured to be disposed withinthe cavity 264 of the spacer member 252. The second mating element 268can include, for example, a ramp, rail, rod, pinion, and/or otherelement configured to engage with and translate relative to the matingelement of the spacer member 252. As illustrated in FIG. 5 , the twosecond mating elements 268 can each include a rail. The second matingelement 268 may also define a path. The path of the second matingelement 268 may be parallel to the path of the first mating element. Thesecond mating element(s) 268 may each have different features (e.g.,length, curvature, and/or angle). The second mating element 268 may becoupled perpendicularly to the fixation member 254. In otherembodiments, the second mating element 268 may be at a non-perpendicularangle (e.g., less than 90°) relative to the fixation member 254. Thefixation member 254 may be angled in any direction relative to thesecond mating element(s) 268 and/or spacer member 252. For example, thefixation member 254 may be angled towards the second side 258 (e.g.,obliquely and/or anterolaterally), as illustrated in FIG. 5 . In otherembodiments, the fixation member 254 may be angled towards an uppersurface 270 or a lower surface (not shown) of the spacer member 252. Thefixation member 254 can include one or more bores 278 extendingtherethrough, wherein each may be configured to receive a fastenertherein. Each bore 278 can include an axis 276. When the device 250 isin an assembled configuration, the axis 276 can be offset (e.g.,anterolaterally and/or obliquely) from the vertical, longitudinal plane274 by an angle β, for example, in the range of from about 5° to about90°. In some embodiments, β may be in the range of from about 5° toabout 45°. In other embodiments, β may be in the range of from about 20°to about 30°. The second mating element 268 may be statically ordynamically (e.g., pivotably and/or articulably) coupled to the fixationmember 254. In use, the fixation member 254 may be configured totranslate at least partially into and out of the cavity 264 of thespacer member 252. This may occur as the mating elements of the spacermember 252 and the fixation member 254 engage each other (e.g., tworails coupled to the fixation member 254 may slide along two trackswithin the cavity 264 of the spacer member 252).

In some embodiments, the device may further include an actuator (notshown). The actuator may be configured to urge translation of thefixation member 254 relative to the spacer member 252. In someembodiments, the actuator may be configured to engage a tool, such as adriver. In other embodiments, the device 250 may further include alocking member (not shown). The locking member may be configured tomaintain the position of the fixation member 254 relative to the spacermember 252. In some embodiments, the locking member may be configured toinhibit retraction of the fixation member 254 towards the cavity 264. Inother embodiments, the mating elements may be configured to inhibitretraction of the fixation member 254. For example, the mating elementsmay include teeth and/or ratcheting.

Embodiments herein are also directed to methods of installing thevertebral fusion device 250. These methods can include providing thevertebral fusion device 250 in a collapsed configuration. In someembodiments, this step can include inserting the vertebral fusion device250 between adjacent vertebrae along a lateral trajectory as describedherein. In the collapsed configuration, the vertebral fusion device 250may include a first width. In some embodiments, the first width may beequal to a width of the spacer member 252 as measured from third side260 to the fourth side 262. An outer surface 272 of the fixation member254 may be a first distance from the third surface 260 of the spacermember 252. Additionally, when in the collapsed configuration, at leasta portion of the mating element 268 may be located within the cavity 264of the spacer member 252. In some embodiments, the fixation member 254may also be partially or completely located within the cavity 264.Furthermore, when in the collapsed configuration, the vertebral fusiondevice 250 may include outer dimensions (e.g., length, width, and/orheight) that are not greater than the outer dimensions of the spacermember 252 alone. When in the collapsed configuration, the device 250may also be fully contained within the intervertebral disc space of apatient.

These methods can also include the step of transitioning the vertebralfusion device 250 from the collapsed configuration to an expandedconfiguration. In the expanded configuration, the device 250 can includea second width that is greater than the first width. The outer surface272 of the fixation member 254 may be at a second distance from thethird surface 260, wherein the second distance is greater than the firstdistance. A portion of the mating element 268 may be located outside thecavity 264. The transitioning step can include translating (e.g.,extending) the fixation member 254 away from the spacer member 252(e.g., anteriorly). This step can be performed by directly urging thefixation member 254 away from the spacer member 252, or indirectly byengaging the actuator. In some embodiments, this step can includesliding the mating element 268 of the fixation member 254 along themating element of the spacer member 252. In some embodiments, thefixation member 254 may translate along an axis that is not parallel tothe horizontal plane of the spacer member 252. In other embodiments, thefixation member 254 may translate, rotate, and/or pivot away from thespacer member 252. In embodiments that include a locking member, thesemethods can also include locking the fixation member 254 in the expandedconfiguration.

Some methods can further include inserting a fastener into bore 278along axis 276. In some embodiments, this step can include inserting thefastener at an angle, relative to the vertical, longitudinal plane 274,in the range of from about 5° to about 90°. In other embodiments, thisstep can include inserting the fastener along an anterolateral and/oroblique trajectory. Advantageously, a user may be able to install thespacer member 252 and fixation member 254 along a first trajectory, andmay be able to install the fastener(s) along a second trajectory. Inuse, when the fastener is installed along an anterolateral and/oroblique trajectory, various anatomical structures may advantageously beavoided, as described herein.

Turning to FIG. 6 , some embodiments herein are directed to a vertebralfusion device 300 that can include a spacer member 302 and a fixationmember 304. The spacer member 302 can include features of the otherspacer members described herein. For example, the spacer member 302 maybe configured for insertion between adjacent vertebrae via a lateralprocedure (e.g., lateral lumbar interbody fusion). The spacer member 302may have a length (e.g., as measured between a leading end 306 and atrailing end 308) that is about 100-300% greater than a width thereof(e.g., as measured in the anterior-posterior direction). The spacermember 302 may also have a length that is configured to laterally span avertebral endplate. For example, the spacer member 302 may have a lengthin the range of from about 40 mm to about 60 mm.

The fixation member 304 can include a base element 310 and a movableelement 312. The base element 310 can include a first (e.g., superior)end 314, a second (e.g., inferior) end 316, a distal surface 318, and aproximal surface 320. The base element 310 can also include at least onebore 322 configured to receive a fastener 323 therethrough. The baseelement 310 can be configured to engage the spacer member 302, forexample, at the trailing end 308 thereof. For example, the base element310 can be statically or dynamically (e.g., pivotably and/orarticulably) engaged with the spacer member 302. In some embodiments,the base element 310 can be integrated with the spacer member 302. Inother embodiments, a coupling member, such as a set screw, can beconfigured to couple the base element 310 with the spacer member 302. Inyet other embodiments, the base element 310 may not be engaged with thespacer member 302.

The movable element 312 can include a fastener portion 330 extendingfrom a coupler portion 328. In some embodiments, when assembled, thefastener portion 330 may be superior to the coupler portion 328, or viceversa. The fastener portion 330 can include a bore 332 configured toreceive a fastener 333 therethrough. The coupler portion 328 can beconfigured to couple and/or engage the base element 310. In someembodiments, the coupler portion 328 can be configured to be at leastpartially received within the base element 310. In other embodiments,the coupler portion 328 may be coupled to the distal surface 318 orproximal surface 320 of the base element 310.

The base element 310 may be configured to be movably coupled with themovable element 312. Accordingly, the base element 310 can include afirst coupling feature 324 that can be configured to engage a secondcoupling feature 326 on the movable element 312. In some embodiments,the first coupling feature 324 may be disposed at the first end 314 ofthe base element 310. In other embodiments, the first coupling feature324 may be disposed at the second end 316 of the base element 310. Thesecond coupling feature 326 may be disposed on the coupler portion 328of the movable element 312. In some embodiments, the first couplingfeature 324 can include a protrusion, such as a prong, pin, bump,tongue, and/or rail, and the second coupling feature 326 can include areceptacle, such as a slot, channel, hole, groove, ledge, and/or track.In other embodiments, the first coupling feature 324 can include areceptacle and the second coupling feature 326 can include a protrusion.In yet other embodiments, the first and second coupling features 324,326 may be coupled via a joint (e.g., a dovetail joint, a tongue andgroove joint, and/or a splice joint). In some embodiments, the secondcoupling feature 326 may be configured to translate (e.g., slide) alongthe first coupling feature 324. In other embodiments, the secondcoupling feature 326 may be configured to pivot about the first couplingfeature 324. As illustrated in FIG. 6 , the first coupling feature 324can include a slot at the first end 314 of the base element, and thesecond coupling feature 326 can include a flange extending from thecoupler portion 328 of the movable element 312. In some embodiments, theslot at the first end 314 of the base element 310 can include the firstcoupling feature 324 therein. In other embodiments, the fixation member304 can include two or more movable elements engaged with the baseelement 310. For example, the fixation member 304 can include an uppermovable element configured to translate superiorly and/or a lowermovable element configured to translate inferiorly.

In use, the fixation member 304 may be configured to reversiblytransition between an extended configuration and a retractedconfiguration. In the retracted configuration, the fixation member 304may have a first height. In some embodiments, the height may be measuredfrom the fastener portion 330 of the movable element 312 to the secondend 316 of the base element 310. The fastener portion 330 may beseparated from the second end 316 by a first distance. In someembodiments, at least a section of the coupler portion 328 may bedisposed within the base element 310. In the extended configuration, thefixation member 304 may have a second height that is greater than thefirst height. The fastener portion 300 may be separated from the secondend 316 by a second distance that is greater than the first distance. Insome embodiments, the section of the coupler portion 328 that wasdisposed within the base element 310 may be outside of the base element310. In some embodiments, the device 300 may also include a lockingmember (not shown). In these embodiments, the locking member may beconfigured to inhibit extension and/or contraction of the movableelement 312. For example, the locking member may include teeth,ratcheting, a fastener, and/or other blocking features.

Also described herein are methods for installing the vertebral fusiondevice 300. These methods can include providing the vertebral fusiondevice 300 in a retracted configuration as described herein. In someembodiments, this step can include inserting the device 300 betweenadjacent vertebrae (e.g., L4-L5 vertebrae) along a lateral trajectory.These methods can also include transitioning the fixation member 304from the retracted configuration to the extended configuration, forexample, by extending the movable element 312. In some embodiments, themovable element 312 can translate (e.g., slide) relative to the baseelement 310. For example, the movable element 312 can telescope at leastpartially out of the base element 310. In other embodiments, this stepcan include pivoting the movable element 312 away from the base element310. This step can be performed by directly urging the movable element312 away from the base element 310, for example, by sliding the movableelement 312 at least partially out of the slot on the base element 310.In other embodiments, this step can be performed indirectly byactivating an actuator engaged with the movable element 312. Inembodiments that include a locking member, the method can also includelocking the fixation member 304 in the extended configuration.

Some methods can further include inserting fastener 323 into bore 322and/or inserting fastener 333 into bore 332. Those skilled in the artmay appreciate that the dynamic capability of the movable element 312can advantageously enable a user to adjust a position of the fastener333 based on the particular anatomy of an individual patient.Accordingly, some methods can further include extending and/orretracting the movable element 312 multiple times so as to calibrateand/or improve the location of fastener placement.

The vertebral fusion devices described herein can be used with one ormore fasteners (e.g., bone screw, anchor, and/or staple). In any ofthese embodiments, a curved fastener can be used. One example isillustrated in FIG. 7A. Turning now to FIG. 7A, some embodiments hereinare directed to a vertebral fusion device 350 that can include a spacermember 352, a fixation member 354, and a curved fastener 356. In someembodiments, the device 350 can also include a straight fastener 374.The spacer member 352 and fixation member 354 can include some or all ofthe features of the spacer members and fixation members describedherein. For example, the spacer member 352 may be configured forinsertion between adjacent vertebrae via a lateral procedure (e.g.,lateral lumbar interbody fusion). The spacer member 352 may have alength (e.g., as measured between a leading end 306 and a trailing end308) that is about 100-300% greater than a width thereof (e.g., asmeasured in the anterior-posterior direction). The spacer member 352 mayalso have a length that is configured to laterally span a vertebralendplate. For example, the spacer member 352 may have a length in therange of from about 40 mm to about 60 mm.

The fixation member 354 can include a first (e.g., superior) end 362, asecond (e.g., inferior) end 364, a distal surface 366, and a proximalsurface 368. The fixation member 354 can also include at least one boreconfigured to receive a fastener therethrough. As illustrated in FIG.7A, the first end 362 can include a first bore 370 and the second end364 can include a second bore 372. The first and/or second bores 370,372 can each include an axis (not shown). In some embodiments, at leastone axis (e.g., the axis of first bore 370) can be perpendicular to thefixation member 354. In other embodiments, at least one axis can beconfigured to be parallel to a vertical, longitudinal plane 351 of thespacer member 352. In some embodiments, the fixation member 354 caninclude a height (e.g., as measured from the first end 362 to the secondend 364) that is greater than a height of the base member 352. In otherembodiments, the height of the fixation member 354 can be less than orequal to the height of the base member 352. In yet other embodiments,the device 350 may have a height that is configured to fit within a discspace.

The fixation member 354 can be configured to engage the spacer member352, for example, at the trailing end 360 thereof. For example, thefixation member 354 can be statically or dynamically (e.g., pivotablyand/or articulably) engaged with the spacer member 352. In someembodiments, the fixation member 354 can be integrated with the spacermember 352. In other embodiments, a coupling member, such as a setscrew, can be configured to couple the fixation member 354 with thespacer member 352. In yet other embodiments, the fixation member 354 maynot be engaged with the spacer member 352.

The curved fastener 356 can include a curved, elongate body 376extending from a head 378. The elongate body 376 can be curved along alongitudinal axis thereof. In use, the elongate body 376 may beconfigured to curve away from the spacer member 352. The elongate body376 may be configured to pass through a bore (e.g., first bore 370and/or second bore 372). Accordingly, the body 376 may have a diameterand/or width that is less than a diameter of first bore 370. The curvedfastener 356 can be any suitable fastener member configured to couple animplant to a bone. For example, the curved fastener 356 can include ananchor, staple, and/or screw. In some embodiments, the body 376 can bethreaded. In other embodiments, the body 376 can include one or morebackout-prevention members, such as teeth and/or ratcheting. The body376 can include a tapered tip. In some embodiments, the curved fastener356 can be cannulated. The head 378 may be enlarged and/or rounded. Inother embodiments, the head 378 may be cylindrical, conical, and/orfrustoconical. The head 378 may be configured to engage the fixationmember 354. For example, the head may be configured to rest within oneof the bores. As illustrated in FIG. 7A, curved fastener 356 can beengaged with the first (e.g., superior) bore 370 and straight fastener374 can be engaged with the second (e.g., inferior) bore 372. In otherembodiments, curved fastener 356 can be engaged with the second (e.g.,inferior) bore 372 and straight fastener 374 can be engaged with thefirst (e.g., superior) bore 370.

Embodiments herein are also directed to methods of installing thevertebral fusion device 350. These embodiments can include providing thedevice 350 as described herein with respect to other vertebral fusiondevices. For example, in some embodiments, this step can includeinserting the device 350 into a space, such as between adjacentvertebrae (e.g., L4-L5 vertebrae), along a lateral trajectory. In someembodiments, the spacer member 352 and the fixation member 354 may becoupled prior to insertion. In other embodiments, the spacer member 352and the fixation member 354 may be coupled after insertion (e.g., insitu). The method can also include inserting the curved fastener 356into the first bore 370 at the first (e.g., superior) end 362 of thefixation member 354. Furthermore, the curved fastener 356 can beinserted along a curved trajectory that is coaxial with the longitudinalaxis of the body 376. In some embodiments, this step can includeinserting the body 376 into a superior vertebra. Those skilled in theart may appreciate that this curved trajectory in the superior vertebramay advantageously be configured to avoid certain anatomical structuresas described herein.

The vertebral fusion devices described herein may include a fastenerconfigured to follow a trajectory that has been selected and/or alteredto avoid certain anatomical structures as described herein. As describedherein with respect to vertebral fusion device 350, in some embodiments,a curved fastener may be included. In an alternative embodiment,illustrated in FIG. 7B, the vertebral fusion device 350 can include one,two, or more fasteners 380 configured for lateral insertion along aposterior angle. The fastener 380 can include an elongate body 382extending from a head 384. The elongate body 382 can extend along axis386 in a straight line. The elongate body 382 can include a lengthconfigured for insertion through bore 370 at an angle to the vertical,longitudinal plane 351. In some embodiments, the elongate body 382 mayhave a length that is less than that of other fasteners (e.g., curvedfastener 356 and/or straight fastener 374). Those skilled in the art mayappreciate that fastener insertion along a posterior angle may entailthe risk of injury to various anatomical structures. However, theshorter length of elongate body 382 may advantageously enable insertionin a posterior direction while inhibiting possible injury that may becaused by a fastener protruding into the body.

In use, after the spacer member 352 and the fixation member 354 havebeen installed, the fastener 380 may be inserted into the first bore 370in a posterior and/or posterolateral direction (e.g., towards posteriorside 388 of spacer member 352). The fastener 380 may also be insertedinto a superior vertebra (e.g., an L4 vertebra). As illustrated in FIG.7B, the fastener 380 may be inserted along a trajectory such that theaxis 386 intersects the vertical, longitudinal plane 351 of the spacermember 352. The axis 386 and the plane 351 may intersect to form anangle γ that can be in the range of from about 5° to about 90°. In otherembodiments, γ can be in the range of from about 5° to about 45°. In yetother embodiments, γ can be in the range of from about 20° to about 30°.In some embodiments, the fastener 380 may be inserted along a trajectorysuch that the distal tip 390 of the fastener 380 does not protrudebeyond the posterior side 388 of the spacer member 352. Those skilled inthe art may appreciate that the use of fastener 380 along this posteriorapproach may enable placement of the fastener while avoiding certainanatomical structures as described herein. In some embodiments, afastener (e.g., curved fastener 356, straight fastener 374, and/orfastener 380) may be also inserted into the second bore 372 and/or aninferior vertebra (e.g., an L5 vertebra).

In some embodiments, one or more bores of a fixation member may beangled to direct the trajectory of a fastener. As illustrated in FIGS.8A-B, vertebral fusion device 400 can include a spacer member 402 and afixation member 404. The spacer member 402 and the fixation member 404can include some or all of the features of the spacer members andfixation members described herein, unless described otherwise. Asillustrated in FIG. 8B, the fixation member 404 can include a first(e.g., superior) end 406, a second (e.g., inferior) end 408, a distalsurface 410, and a proximal surface 412. The first end 406 can include afirst bore 414 and the second end 408 can include a second bore 416. Insome embodiments, the first and/or second ends 406, 408 can include twoor more bores. As illustrated in FIG. 8A, for example, the first end 406can include first bore 414 and bore 418. The first bore 414 can includean axis 420 that can be non-perpendicularly angled relative to thespacer member 402 and/or the fixation member 404. As illustrated in FIG.8A, axis 420 can be configured to intersect a vertical, longitudinalplane 422 of the spacer member 352. Axis 420 may extend in a posteriorand/or posterolateral direction (e.g., towards posterior side 426 ofspacer member 402). The axis 420 and the plane 422 may intersect to forman angle (not shown) that can be in the range of from about 5° to about90°. In other embodiments, the angle can be in the range of from about5° to about 45°. In yet other embodiments, the angle can be in the rangeof from about 20° to about 30°. As illustrated in FIG. 8B, axis 420 canalso be configured to intersect a horizontal, longitudinal plane 424 ofthe spacer member 352. Axis 420 may extend in an upward or superiordirection (e.g., away from superior surface 428 of the spacer member402). The axis 420 and the plane 424 may intersect to form an angle δthat can be in the range of from about 5° to about 90°. In otherembodiments, δ can be in the range of from about 5° to about 45°. In yetother embodiments, δ can be in the range of from about 20° to about 30°.Any other bores disposed on the fixation member 404 (e.g., bore 418) caninclude an axis having a similar trajectory as described with respect toaxis 420.

In use, after the spacer member 402 and the fixation member 404 havebeen installed, a fastener 430 may be inserted into the first bore 414along axis 420. As illustrated in FIGS. 8A-B, a curved fastener (e.g.,curved fastener 356) may be inserted therein. In other embodiments, astraight fastener may be used. The fastener may be a screw, anchor,and/or staple. The fastener may be inserted from an anterolateral and/oroblique position, and may extend posteriorly and/or posterolaterally.Advantageously, the angled axis 420 of bore 414 can direct a fasteneraway from certain anatomical structures as described herein, including,without limitation, the iliac crest, psoas major, dura, and/or lumbarplexus.

Turning now to FIG. 9 , an alternative embodiment of a vertebral fusiondevice is illustrated. Vertebral fusion device 450 can include a spacermember 452, a fixation member 454, and a clamp member 456. The spacermember 452 and fixation member 454 can include some or all of thefeatures of the spacer members and fixation members described herein.For example, the spacer member 452 may be configured for insertionbetween adjacent vertebrae via a lateral procedure (e.g., lateral lumbarinterbody fusion). The spacer member 452 may have a length (e.g., asmeasured between a leading end and a trailing end) that is about100-300% greater than a width thereof (e.g., as measured in theanterior-posterior direction). The spacer member 452 may also have alength that is configured to laterally span a vertebral endplate. Forexample, the spacer member 452 may have a length in the range of fromabout 40 mm to about 60 mm. The spacer member 452 can also include aplurality of horizontal grooves at a trailing end thereof. In someembodiments, the grooves can be disposed on a proximal surface and/or onan inner surface of the spacer member 452. Each groove can include anon-symmetrical slope. For example, each groove can be slanted, tapered,and/or sawtooth-shaped. The grooves can be configured to engage theclamp member 456 as described further herein.

In some embodiments, the spacer member 452 may be configured to engagethe fixation member 454. The fixation member 454 can include a first(e.g., superior) end 458 and a second (e.g., inferior) end 460. Thefixation member 454 can also include at least one bore configured toreceive a fastener therethrough. As illustrated in FIG. 9 , the secondend 460 can include a single bore 462 therethrough. In some embodiments,the fixation member 454 may include only one bore. In other embodiments,the first end 458 may not include any bores. In yet other embodiments,the second end 460 may not include any bores. In some embodiments, thefixation member 454 can include a height (e.g., as measured from thefirst end 458 to the second end 460) that is greater than a height ofthe spacer member 452. In other embodiments, the height of the fixationmember 454 can be less than or equal to the height of the spacer member452. In yet other embodiments, the device 450 may have a height that isconfigured to fit within a disc space (e.g., between two adjacentvertebrae).

The clamp member 456 can include first and second prongs 464, 466extending generally perpendicularly from a body portion 468. The bodyportion 468 can be straight or curved. In some embodiments, the bodyportion 468 may be curved. In some embodiments, the body portion 468 mayinclude a radius of curvature that is greater than that of a fastenerbody and not larger than that of a fastener head. The body portion 468and first and second prongs 464, 466 may define a U-shaped opening 470.Each prong 464, 466 can include a tip 472, 474 having a retentionfeature 476, 478 thereon. The retention feature 476, 478 may include aprojection angled away from the tip, such as a sawtooth, barb, orratchet. The retention feature 476, 478 may be configured to engage thegrooves on the spacer member 452.

Also described herein are methods for installing the vertebral fusiondevice 450. These embodiments can include providing the device 450 asdescribed herein with respect to other vertebral fusion devices. Forexample, in some embodiments, this step can include inserting the device450 into a space, such as between adjacent vertebrae (e.g., L4-L5vertebrae), along a lateral trajectory. In some embodiments, the spacermember 452 and the fixation member 454 may be coupled prior toinsertion. In other embodiments, the spacer member 452 and the fixationmember 454 may be coupled after insertion (e.g., in situ). A fastener480 can be inserted into the bore 462 on the second end 460 of thefixation member 454. Any of the fasteners described herein can be used.In some embodiments, this step can include inserting the fastener 480into an inferior vertebra.

Methods described herein can also include placing the clamp member 456above the fixation member 454. In some embodiments, this step caninclude superficially placing the clamp member 456 on a surface (e.g., alateral surface) of a superior vertebra. A fastener 482 can then beinserted within the U-shaped opening 470 of the clamp member 456. Thefastener 482 may also be inserted above the fixation member 454. Thoseskilled in the art may appreciate that the fastener 482 may not beinserted into a bore in the fixation member. Advantageously, thisfeature may provide a user with greater flexibility with regardingfastener placement. The methods can also include translating (e.g.,compressing) the clamp member 456 towards the spacer member 452 untilthe retention features 476, 478 of the clamp member 456 engage thegrooves on the spacer member 452. Those skilled in the art mayappreciate that features of the clamp member 456 and the spacer member452 may form a ratcheting mechanism, wherein the grooves of the spacermember 452 enable translation of the clamp member 456 towards spacermember (e.g., in an inferior and/or downward direction) and inhibittranslation of the clamp member 456 in the reverse direction (e.g.,superior and/or upward). Additionally, the head of the fastener member482 may inhibit lateral motion of the clamp member 456. In otherembodiments, those skilled in the art may appreciate that the fixationmember 454 can include a bore at the first end 458 only, and the clampmember 456 can be placed below the fixation member 454 (e.g., on aninferior vertebra).

Turning to FIGS. 10A-B, an alternative embodiment of a vertebral fusiondevice is illustrated. Vertebral fusion device 500 can include a spacermember 502. The vertebral fusion device 500 can also include a fastener506. The spacer member 502 can include some or all of the features ofthe spacer members described herein, unless described otherwise. Asillustrated in FIGS. 10A-B, the spacer member 502 can include a leadingend 508, a trailing end 510, a first (e.g., anterior) side 512, a second(e.g., posterior) side 514, an upper (e.g., superior) side 516, and alower (e.g., inferior) side 518. The spacer member 502 may be configuredfor insertion between adjacent vertebrae via a lateral procedure (e.g.,lateral lumbar interbody fusion). The spacer member 502 may have alength (e.g., as measured between leading end 508 and trailing end 510)that is about 100-300% greater than a width thereof (e.g., as measuredin the anterior-posterior direction). The spacer member 502 may alsohave a length that is configured to laterally span a vertebral endplate.For example, the spacer member 502 may have a length in the range offrom about 40 mm to about 60 mm.

The spacer member 502 may also include a receptacle 520 (e.g., a boreand/or channel) configured to receive at least a portion of fastener 506therethrough, as illustrated in FIG. 10B. In some embodiments, thereceptacle 520 can include an opening on the upper and/or lower sides516, 518. In other embodiments, the receptacle 520 can include anopening on the first and/or second sides 512, 514. The receptacle 520can include an axis 526. In some embodiments, the axis 526 can begenerally straight; in other embodiments, the axis 526 can be generallycurved. As illustrated in FIG. 10B, the axis 526 can be offset from avertical plane (e.g., longitudinal vertical plane 522 and/or transversevertical plane 524) of the spacer member 502. The axis 526 may be offsetfrom a vertical plane of the spacer member 502 by an angle in the rangeof from about 5° to about 90°. In some embodiments, the axis 526 may beoffset from a vertical plane of the spacer member 502 by an angle in therange of from about 5° to about 45°. In other embodiments, the axis 526may be offset from a vertical plane of the spacer member 502 by an anglein the range of from about 20° to about 30°. In some embodiments, theaxis 526 can intersect a vertical plane of the spacer member 502. Thespacer member 502 can include a locking member and/or a retentionmember, such as ratcheting, teeth, barbs, and/or blades, which can beconfigured to retain the fastener 506 therein.

The vertebral fusion device 500 may or may not include a fixation member(not shown). In some embodiments, the spacer member 502 may beconfigured to engage a fixation member. In some embodiments, thefixation member may be configured to engage one or more areas of thespacer member 502, such as the leading end 508, trailing end 510, firstside 512, second side 514, upper side 516, and/or lower side 518. Insome embodiments, the fixation member may be configured to engage anouter surface of the spacer member 502. In other embodiments, thefixation member may be configured to engage an inner surface of thespacer member 502. The fixation member can include one or moredimensions (e.g., length, width, and/or height) that are not larger thanthat of the spacer member 500. The fixation member may be generally flatand/or planar. The fixation member may include a bore passingtherethrough, and may be configured to receive the fastener 506 therein.

The spacer member 502 may be configured to engage (e.g., receive) thefastener 506. As illustrated in FIG. 10A, the fastener 506 can includean elongate body 528 extending from a head 530. The fastener 506 caninclude a screw, anchor, and/or staple. The fastener 506 can include oneor more features of the fasteners described herein. The elongate body528 can be threaded. The elongate body 528 can be configured to passthrough the bore 520 of the spacer member 502. The elongate body 528 canhave a length that can be configured to be greater than anintervertebral space, as illustrated in FIG. 10A. The length of theelongate body 528 can be greater than the height of the spacer member502. As illustrated in FIG. 10A, the elongate body 528 can be configuredto engage two adjacent vertebral bodies.

Embodiments herein are also directed to methods of installing thevertebral fusion device 500. These methods can include providing thedevice 500 as described herein with respect to other vertebral fusiondevices. For example, in some embodiments, this step can includeinserting the device 500 into a space, such as between adjacentvertebrae (e.g., L4-L5 vertebrae), along a lateral trajectory. Methodsdescribed herein can also include the step of inserting the fastener 506through the bore 520 of the spacer member 502. In some embodiments, whenthe fastener 506 is inserted, it can extend above and below the device500 (e.g., beyond upper and lower sides 516, 518). In other embodiments,when the fastener 506 is inserted, it can be located within a perimeterof the device 500 (e.g., within the leading end 508, trailing end 510,first side 512, and second side 514). In some embodiments, this step caninclude inserting the fastener 506 through an inferior vertebra, thedevice 500, and a superior vertebra. In other embodiments, this step caninclude inserting the fastener 506 through a superior vertebra, thedevice 500, and an inferior vertebra. In some embodiments, the fastener506 can be inserted from an anterolateral and/or oblique position (e.g.,between a direct lateral and direct anterior point of entry). In otherembodiments, the fastener 506 can be inserted from a position anteriorto the iliac crest. Advantageously, those skilled in the art mayappreciate that these approaches may enable retention of the device 500between adjacent vertebral bodies while avoiding certain anatomicalstructures. Some embodiments can also include locking the fastener 506relative to the spacer member 502. This step can include actuating thelocking member. In other embodiments, a retention member may retain thefastener 506 relative to the spacer member 502 without a separateactuation step.

Turning now to FIGS. 11A-B, an alternative embodiment of a vertebralfusion device is illustrated. Vertebral fusion device 550 can include aspacer member 552 and a fixation member 554. The spacer member 552 andthe fixation member 554 can include some or all of the features of thespacer members and fixation members herein, unless described otherwise.For example, the spacer member 552 may be configured for insertionbetween adjacent vertebrae via a lateral procedure (e.g., lateral lumbarinterbody fusion). The spacer member 552 may have a length (e.g., asmeasured between a leading end and a trailing end) that is about100-300% greater than a width thereof (e.g., as measured in theanterior-posterior direction). The spacer member 552 may also have alength that is configured to laterally span a vertebral endplate. Forexample, the spacer member 552 may have a length in the range of fromabout 40 mm to about 60 mm. As illustrated in FIGS. 11A-B, the spacermember 552 can also include one or more retention members 556. In someembodiments, the spacer member 552 can include a plurality of retentionmembers 556. Each retention member 556 can be configured to urge,encourage, and/or retain the vertebral fusion device 550 within anintervertebral space. In some embodiments, each retention member 556 caninclude a spike, anchor, and/or shim. Advantageously, the retentionmember(s) 556 can be deployable, extendable, and/or expandable. In someembodiments, the retention member(s) 556 may be located within thespacer member 552. Each retention member 556 may be configured totransition between a retracted state, wherein the retention member 556is contained within the spacer member 552, to a deployed state, whereinat least a portion of the retention member 556 is protruding beyond thespacer member 552. In some embodiments, the spacer member 552 caninclude one or more holes, for example, on upper surface 558, throughwhich the retention member(s) 556 can pass. In other embodiments, thedevice 550 can further include an actuator (not shown) that can beconfigured to deploy and/or retract the retention member(s) 556.

In some embodiments, the spacer member 552 may be configured to engagethe fixation member 554. In these embodiments, the fixation member 554may be configured to statically or dynamically (e.g., pivotably and/orarticulably) engage the spacer member 552 as described herein. Thefixation member 554 can include a first (e.g., superior) end 560 and asecond (e.g., inferior) end 562. The fixation member 554 can alsoinclude at least one bore configured to receive a fastener therethrough.As illustrated in FIGS. 11A-B, the second end 562 can include a singlebore 564 therethrough. In some embodiments, the fixation member 554 mayinclude only one bore. In other embodiments, the first end 560 may notinclude any bores. In yet other embodiments, the second end 562 may notinclude any bores. In some embodiments, the fixation member 554 caninclude a height (e.g., as measured from the first end 560 to the secondend 562) that is greater than a height of the spacer member 552 (e.g.,as measured between the upper surface 558 and lower surface 559). Inother embodiments, the height of the fixation member 554 can be lessthan or equal to the height of the spacer member 552. When in anassembled configuration, as illustrated in FIGS. 11A-B, the first end560 may not extend beyond the upper surface 558 of the spacer member552, while the second end 562 may extend beyond the lower surface 559 ofthe spacer member 552.

Also described herein are methods for installing the vertebral fusiondevice 550. These embodiments can include providing the device 550 asdescribed herein with respect to other vertebral fusion devices. Forexample, in some embodiments, this step can include inserting the device550 into a space, such as between adjacent vertebrae (e.g., L4-L5vertebrae), along a lateral trajectory. In some embodiments, the spacermember 552 and the fixation member 554 may be coupled prior toinsertion. In other embodiments, the spacer member 552 and the fixationmember 554 may be coupled after insertion (e.g., in situ). The vertebralfusion device 550 may be provided with the retention member(s) 556 in aretracted configuration. In this configuration, the retention member(s)556 may be retained within the spacer member 552. A fastener 566 can beinserted into the bore 564 on the second end 562 of the fixation member554. Any of the fasteners described herein can be used. In someembodiments, this step can include inserting the fastener 566 into aninferior vertebra. The methods can also include transitioning theretention member(s) 556 from the retracted configuration to the deployedconfiguration. This step can include deploying, extending, and/orexpanding the retention member(s) 556 so that they are at leastpartially protruding beyond an outer surface (e.g., upper surface 558)of the spacer member 552. This step can also include engaging (e.g.,gripping, biting, penetrating, and/or piercing) a superior vertebra withthe retention member(s) 556. Those skilled in the art may appreciatethat because the device 550 uses internal retention member 556 to engagethe superior vertebra, a user advantageously may avoid interference fromthe iliac crest and other anatomical features.

Turning now to FIGS. 12A-F, an alternative embodiment of a vertebralfusion device is illustrated. Unless otherwise described herein,vertebral fusion device 600 can include some or all of the features ofthe vertebral fusion devices described in U.S. patent application Ser.No. 14/449,428, entitled “VARIABLE LORDOSIS SPACER AND RELATED METHODSOF USE,” filed Aug. 1, 2014, U.S. Patent Publication No. 2014/0163683,entitled “EXPANDABLE VERTEBRAL IMPLANT,” published Jun. 12, 2014, andU.S. Patent Publication No. 2013/0023993, entitled “EXPANDABLE FUSIONDEVICE AND METHOD OF INSTALLATION THEREOF,” published Jan. 23, 2013, allof which are hereby incorporated by reference herein in their entiretiesfor all purposes. Vertebral fusion device 600 can include a first (e.g.,upper and/or superior) endplate 602, a second (e.g., lower and/orinferior) endplate 604, a first engagement, angled, or ramped body 606,and a second engagement, angled or ramped body 608. As illustrated inFIG. 12C, the device 600 can also include a first side 601 and a secondside 603. As described further herein, vertebral fusion device 600 caninclude an adjustable height and/or lordotic angle. In theseembodiments, the first and/or second endplates 602, 604 may beconfigured to pivot about a pivot point, as described herein withrespect to vertebral fusion device 800. The vertebral fusion device 600may be wedge-shaped along a latitudinal axis. For example, the device600 may have a height that increases from the first side 601 to thesecond side 603. In some embodiments, the first and/or second rampedbodies 606, 608 may be wedge-shaped.

First endplate 602 can include a body portion that can include a first(e.g., leading and/or distal) end 610 a second (e.g., trailing and/orproximal) end 612, a first (e.g., posterior) side 618, and a second(e.g., anterior) side 620. The body portion of the first endplate 602can also include an outer surface 614, an inner surface 616, an uppersurface 622, and a lower surface 628. As illustrated in FIG. 12A, theupper surface 622 can include a plurality of protrusions (e.g., bumps,teeth, and/or peaks) configured to engage a vertebral body. The uppersurface 622 can be generally planar, concave, and/or convex. The firstendplate 602 can include one or more mating features 624. In someembodiments, the mating feature(s) 624 may be located on the innersurface 616. In other embodiments, the first side 618 may include atleast one mating feature 624, and the second side 620 may include atleast one mating feature 624. In yet other embodiments, the first and/orsecond sides 618, 620 can each include a mating feature at the first end610, a mating feature at an intermediate portion, and a mating featureat the second end 612.

As illustrated in FIG. 12A, the first endplate 602 can also include afirst extension portion 648. The first extension portion 648 can extend,e.g., vertically, from the second end 612 of the body portion of thefirst endplate 602. The first extension portion 648 can have a heightthat is greater than a height of the body portion of the first endplate602. For example, the first extension portion 648 may extend beyond theupper surface 622. In some embodiments, the first extension portion 648may be coupled (e.g., attached, joined, and/or connected) to the firstendplate 602. In some embodiments, the first extension portion 648 maybe moveably (e.g., articulably) coupled to the body portion of the firstendplate 602, for example, as described herein with respect to vertebralfusion device 50. For example, the body portion of the first endplate602 and the extension portion 648 may together form a dovetail joint. Insome embodiments, the first extension portion 648 and the body portionof first endplate 602 may each include a different material (e.g., ametal and/or a polymer). In other embodiments, the first extensionportion 648 and the body portion of the first endplate 602 may form aunitary body. The first extension portion 648 can include a bore 650passing therethrough. The bore 650 can be configured to receive afastener 651 therein. The first extension portion 648 can also include areceptacle 654. The receptacle 654 may at least partially overlap thebore 650. The receptacle 654 may be configured to receive a retentionmember 656 therein.

As illustrated in FIG. 12B, the bore 650 can include an axis 652. Insome embodiments, axis 652 may be generally parallel to a longitudinalaxis (e.g., midline) 626 of the first endplate 602. In otherembodiments, axis 652 may be skewed relative to the longitudinal midline626. In yet other embodiments, axis 652 may be configured to intersect avertical, longitudinal plane 658 of the assembled device 600, asillustrated in FIG. 12C. In some embodiments, the axis 652, bore 650,and/or first extension portion 648 may be horizontally offset from thelongitudinal midline 626 and/or vertical, longitudinal plane 658. Insome embodiments, the axis 652, bore 650, and/or first extension portion648 may be horizontally offset towards the second side 620. Asillustrated in FIG. 12C, the axis 652 can intersect the plane 658 by anangle ε. In some embodiments, ε can be in the range of from about 0° toabout 90°. In other embodiments, ε can be in the range of from about 5°to about 45°. In yet other embodiments, ε can be in the range of fromabout 20° to about 30°. In some embodiments, another angle γ can beprovided, as shown in FIG. 12B. In some embodiments, axis 652 can bearranged from 0-90 degrees off angle γ.

Second endplate 604 can include some or all of the same features as thefirst endplate 602. In some embodiments, the first and second endplates602, 604 may be symmetrical with respect to each other. As illustratedin FIG. 12A, second endplate 604 can include a body portion that caninclude a first (e.g., leading and/or distal) end 630, a second (e.g.,trailing and/or proximal) end 632, a first (e.g., posterior) side 634,and a second (e.g., anterior) side 636. The body portion of the secondendplate 604 can also include an outer surface 638, an inner surface640, an upper surface 642, and a lower surface 644. The lower surface644 can include a plurality of protrusions (e.g., bumps, teeth, and/orpeaks) configured to engage a vertebral body. The lower surface 644 canbe generally planar, concave, and/or convex. The second endplate 604 caninclude one or more mating features 646. In some embodiments, the matingfeature(s) 646 may be located on the inner surface 640. In otherembodiments, the first side 634 may include at least one mating feature646, and the second side 636 may include at least one mating feature646. In yet other embodiments, the first and/or second sides 634, 636can each include a mating feature at the first end 630, a mating featureat an intermediate portion, and a mating feature at the second end 632.

As illustrated in FIG. 12A, the second endplate 604 can also include asecond extension portion 660. The second extension portion 660 canextend, e.g., vertically, from the second end 632 of the body portion ofthe second endplate 604. The second extension portion 660 can have aheight that is greater than a height of the body portion of the secondendplate 604. For example, the second extension portion 660 may extendbeyond the lower surface 644. In some embodiments, the second extensionportion 660 may be coupled (e.g., attached, joined, and/or connected) tothe body portion of the second endplate 604. In some embodiments, thesecond extension portion 660 may be articulably coupled to the bodyportion of the second endplate 604, for example, as described hereinwith respect to vertebral fusion device 50. For example, the bodyportion of the second endplate 604 and the second extension portion 660may together form a dovetail joint. In some embodiments, the secondextension portion 660 and the body portion of the second endplate 604may each include a different material (e.g., a metal and/or a polymer).In other embodiments, the second extension portion 660 and the bodyportion of the second endplate 604 may form a unitary body. The secondextension portion 660 can include a bore 662 passing therethrough. Thebore 662 can be configured to receive a fastener 663 therein. The secondextension portion 660 can also include a receptacle 664. The receptacle664 may at least partially overlap the bore 662. The receptacle 664 maybe configured to receive a retention member 666 therein.

As illustrated in FIG. 12B, the bore 662 can include an axis 668. Insome embodiments, axis 668 may be generally parallel to a longitudinalaxis (e.g., midline) 670 of the second endplate 604. In otherembodiments, axis 668 may be skewed relative to the longitudinal midline670. In yet other embodiments, axis 668 may be configured to intersect avertical, longitudinal plane (not shown) of the second endplate 604,which may be coplanar with the vertical, longitudinal plane 658 of thefirst endplate 602. In some embodiments, the axis 668, bore 662, and/orsecond extension portion 660 may be horizontally offset from thelongitudinal midline 670 and/or vertical, longitudinal plane. In someembodiments, the axis 668, bore 662, and/or second extension portion 660may be horizontally offset towards the second side 636. In someembodiments, the axis 668 can intersect the plane (e.g., including plane658) by an angle. In some embodiments, the angle can be in the range offrom about 0° to about 90°. In other embodiments, the angle can be inthe range of from about 5° to about 45°. In yet other embodiments, theangle can be in the range of from about 20° to about 30°. In still otherembodiments, the angle can be equal to c as described herein.

As illustrated in FIG. 12B, mating feature 624 of the first endplate 602may be inclined (e.g., may extend from lower surface 628 towards uppersurface 622) along longitudinal axis 626 in a direction from the secondend 612 towards the first end 610. In some embodiments, mating feature624 may be angled, e.g., towards the first end 610. In otherembodiments, mating feature 624 may be inclined along the longitudinalaxis 626 in a direction from the first end 610 towards the second end612. In some embodiments, mating feature 646 of the second endplate 604may be declined (e.g., may extend from upper surface 642 towards lowersurface 644) along longitudinal axis 670 in a direction from the secondend 632 towards the first end 640. In some embodiments, mating feature646 may be angled, e.g., towards the first end 630. In otherembodiments, mating feature 646 may be declined along the longitudinalaxis 670 from the first end 630 towards the second end 632.

As described further herein, the first and/or second endplates 602, 604may be configured to engage (e.g., mate with) the first ramped body 606.As illustrated in FIG. 12A, the first ramped body 606 can include afirst (e.g., leading and/or distal) end 672, a second (e.g., trailingand/or proximal) end 674, a first (e.g., posterior) side portion 676,and a second (e.g., anterior) side portion 678. As illustrated in FIG.12B, the first ramped body 606 can also include a third (e.g., superior)end 680 and a fourth (e.g., inferior) end 682. The third end 680 mayinclude one or more mating features 684 configured to engage the firstendplate 602 and the fourth end 682 may include one or more matingfeatures 686 configured to engage the second endplate 604. The firstside portion 676 and/or the second side portion 678 can include one ormore mating features 684, 686 configured to engage the first and/orsecond endplates 602, 604. In some embodiments, the first end 672 caninclude two or more mating features 684 on the third end 680 and two ormore mating features 686 on the fourth end 682. Each of the matingfeatures of the first ramped body 606 may be configured (e.g., shaped)to mate with a corresponding mating feature 624, 646 on the first and/orsecond endplates 602, 604. Mating features 684, 686 may havesubstantially similar inclinations, when in an assembled configuration,as their corresponding mating features 624, 646. In some embodiments,each mating feature 684 is inclined towards the first end 672 of thefirst ramped body 606, and each mating feature 686 is declined towardsthe first end 672 of the first ramped body 606. In other embodiments,mating feature 684 and mating feature 686 may diverge from each otheralong a longitudinal axis from a position relatively adjacent to thesecond end 674 to a position relatively adjacent to the first end 672.In yet other embodiments, the mating features 684, 686 may be angled,e.g., towards the first end 672. In still other embodiments, one or moremating features 684 may be inclined towards the second end 674 of theramped body 606 and/or one or more mating features 686 may be declinedtowards the second end 674 of the ramped body 606. In some embodiments,one or more mating features 684, 686 can include a protrusion (e.g., atongue, rail, and/or shoulder). In other embodiments, one or more matingfeatures 684, 686 can include a recess (e.g., a groove, track, and/orchannel). In some embodiments, for example, as illustrated in FIG. 12B,the mating features 684, 686 can alternate longitudinally along thefirst and/or second sides 676, 678. In other embodiments, for example,as illustrated in FIG. 12 B, the mating features 684, 686 can alternatetransversely along the first and/or second sides 676, 678. Each matingfeature 684 on the first ramped body 606 can be generally the same. Eachmating feature 686 may be generally the same. In some embodiments, atleast one mating feature 684 and/or 686 may include different propertiesas compared to the other mating features 684, 686.

The mating features 624, 646 on the first and/or second endplates 602,604 as described herein may be configured to form a slidable joint witha corresponding mating feature 684 686 on the first ramped body 606.Accordingly, the first ramped body 606 may be configured to slideablyengage the first and/or second endplates 602, 604. The slideable jointmay advantageously enable the vertebral fusion device 600 to transitionreversibly between expanded and contracted configurations. The slidablejoint may include, for example, a tabled splice joint, a dovetail joint,a tongue and groove joint, or another suitable joint. In someembodiments, one or more mating features on the first and/or secondendplates 602, 604 can include a recess (e.g., a groove, track, and/orchannel), and one or more mating features on the first ramped body 606can include a protrusion (e.g., a tongue, rail, and/or shoulder)configured to slide within the groove. In other embodiments, one or moremating features on the first and/or second endplates 602, 604 caninclude a protrusion and one or more mating features on the first rampedbody 606 can include a recess.

As illustrated in FIG. 12A, the second end 674 of the first ramped body606 can include a first threaded bore 688 passing longitudinallytherethrough. The first threaded bore 688 may be configured to receive(e.g., threadably engage) a threaded member 704 of an actuator 702. Asillustrated in FIG. 12A, the threaded member 704 of the actuator 702 caninclude a proximal end having a tool-engaging recess 710. As illustratedin FIGS. 12A-B, the actuator 702 can also include a washer 706 and/or asnap ring 708. The second end 674 of the first ramped body 606 can alsoinclude a second bore 690 passing longitudinally therethrough. In someembodiments, the second bore 690 may be threaded. The second bore 690may be configured to engage an inserter. In other embodiments, thesecond bore 690 can advantageously be configured for use as an accessport to enable graft material to be delivered into a cavity 692(illustrated in FIG. 12C) of the device 600. The second bore 690 may belaterally displaced from the first threaded bore 688. In someembodiments, the first threaded bore 688 may be located adjacent to thesecond side 678 of the first ramped body 606 and the second bore 690 maybe located adjacent to the first side 676, or vice versa. In otherembodiments, the first threaded bore 688 may be anteriorly offsetrelative to the second bore 690, or vice versa. In some embodiments,illustrated in FIG. 12E, the second bore 690 can be located adjacent tothe second side 678 and/or anteriorly offset relative to the firstthreaded bore 688. In these embodiments, the device 600 may beadvantageously configured to engage an inserter at an angle offset fromthe plane 658, thereby enabling a user to position the device 600 in adirect lateral orientation, e.g., in a patient's lumbar spine, whilereducing interaction with the psoas muscle.

The first threaded bore 688 and/or the second bore 690 can include anaxis that is horizontally offset from the vertical, longitudinal plane658. In some embodiments, the axis (e.g., of the first threaded bore 688and/or the second bore 690) can be horizontally offset towards thesecond side 678. In some embodiments, the axis of the first threadedbore 688 and/or the second bore 690 can intersect the plane 658 to forman angle. In some embodiments, the angle can be in the range of fromabout 0° to about 90°. In other embodiments, the angle can be in therange of from about 5° to about 45°. In yet other embodiments, the anglecan be in the range of from about 20° to about 30°. In still otherembodiments, the angle can be equal to c as described herein.

When in an assembled configuration, the second ramped body 608 can bedisposed adjacent to the first ramped body 606. Second ramped body 608can include one or more mating features configured to engagecorresponding mating features 624, 646 on the first and/or secondendplates 602, 604. The mating features on the second ramped body 608can include some or all of the same features as the mating features 684,686 of the first ramped body 606. As illustrated in FIG. 12A, the secondramped body 608 can include a first bore 694. The first bore 694 can beconfigured to be coaxial with the first threaded bore 688 of the firstramped body 606 when in an assembled configuration. The first bore 694may be configured to receive the head portion of the actuator 702therein. In use, the head portion may be configured to rotate within thefirst bore 694. The second ramped body 608 can also include a secondbore 696. The first and/or second bores 694, 696 may be threaded. Insome embodiments, the second bore 696 can be configured to engage aninserter. The second bore 696 can be configured to be coaxial with thesecond bore 690 of the first ramped body 606 when in an assembledconfiguration. The second bore 696 can be laterally displaced from thefirst bore 694. In some embodiments, the first bore 694 may be locatedadjacent to a second side 698 of the second ramped body 606 and thesecond bore 696 may be located adjacent to a first side 697, or viceversa. In other embodiments, the first bore 694 may be anteriorly offsetrelative to the second bore 696, or vice versa. In some embodiments,illustrated in FIG. 12E, the second bore 696 can be located adjacent tothe second side 698 and/or anteriorly offset relative to the first bore694. In these embodiments, the device 600 may be advantageouslyconfigured to engage an inserter at an angle offset from the plane 658,thereby enabling a user to position the device 600 in a direct lateralorientation, e.g., in a patient's lumbar spine, while reducinginteraction with the psoas muscle.

The first bore 694 and/or the second bore 696 can include an axis thatis horizontally offset from the vertical, longitudinal plane 658. Insome embodiments, the axis of the first bore 694 and/or the second bore696 can be horizontally offset towards the second side 698. In someembodiments, the axis of the first bore 694 and/or the second bore 696can intersect the plane 658 to form an angle. In some embodiments, theangle can be in the range of from about 0° to about 90°. In otherembodiments, the angle can be in the range of from about 5° to about45°. In yet other embodiments, the angle can be in the range of fromabout 20° to about 30°. In still other embodiments, the angle can beequal to ε as described herein.

The vertebral fusion device 600 can advantageously include an adjustableheight and/or lordotic angle. In some embodiments, the device 600 may beexpandable. The vertebral fusion device 600 may advantageously beconfigured to reversibly transition between a collapsed configurationand an expanded configuration. In the collapsed configuration, forexample, as illustrated in FIG. 12D, the vertebral fusion device 600 caninclude a first height (e.g., as measured from the upper surface 622 ofthe first endplate 602 to the lower surface 644 of the second endplate604). In the expanded configuration, for example, as illustrated in FIG.12F, the vertebral fusion device 600 can include a second height that isgreater than the first height. In some embodiments, the second heightcan be from about 25% to about 200% greater than the first height. Inother embodiments, the second height can be from about 100% to about150% greater than the first height. In some embodiments, the firstheight can be in the range of from about 5 mm to about 10 mm, and/or thesecond height can be in the range of from about 15 mm to about 20 mm. Insome embodiments, the change in height can be caused by movement of thefirst and second endplates 602, 604 towards and/or away from each other.In these embodiments, the first and second endplates 602, 604 can beseparated by a first distance when in the collapsed configuration and asecond distance when in the expanded configuration, wherein the seconddistance is greater than the first distance. Those skilled in the artmay appreciate that, in use, the height of the vertebral fusion device600 can be adjusted to accommodate an individual patient's anatomy.Additionally, the device 600 may be inserted into an intervertebralspace in the collapsed configuration, which may entail less trauma tosurrounding tissue due to its smaller size.

Embodiments herein are also directed to methods of installing thevertebral fusion device 600. Methods can include providing the device600 in the collapsed configuration, for example, as illustrated in FIG.12D. In some embodiments, this step can include providing (e.g.,inserting) the device 600 between two adjacent vertebrae (e.g., betweenthe L4 and L5 vertebrae). In some embodiments, the device 600 can beinserted using an inserter, such as a straight inserter or an angledinserter. In these embodiments, the methods of installation can includecoupling the inserter with the device 600, for example, threading athreaded member of the inserter into the second bore 690, 696 of thefirst and/or second ramps 606, 608. In some embodiments, the device 600may be inserted along a lateral approach, for example, when a straightinserter is used. In other embodiments, the device 600 can be insertedalong an anterolateral and/or oblique approach, for example, when anangled inserter is used. In these embodiments, the device 600 can besubsequently pivoted into a lateral orientation while in theintervertebral space. In some embodiments, the device 600 may beinserted using minimally invasive methods. In some embodiments, theintervertebral space may be prepared beforehand, for example, byperforming a discectomy to remove some or all of the intervertebraldisc.

Methods herein can also include expanding the device 600, for example,by transitioning the device 600 from the collapsed configuration to theexpanded configuration. To expand the device 600, the second ramped body608 may be moved towards the first ramped body 606, or vice versa. Asthe first and second ramps 606, 608 translate towards each other, therespective mating features of the first and second ramps 606, 608 maypush against corresponding mating features on the first and secondendplates 602, 604, thereby pushing the first and second endplates 602,604 apart and increasing the height of the device 600.

In some embodiments, the step of expanding the device 600 can includeactuating the actuator 702. This step can include applying a rotationalforce to the threaded member 704 to threadably engage the first rampedbody 606. The rotational force can be added directly (e.g., manually)and/or indirectly (e.g., through a driver or other tool). In someembodiments, as the threaded member 704 is rotated in a first direction,the threaded member 704 may pull the first ramped body 606 towards thesecond ramped body 608. As the first ramped body 606 moves towards thesecond ramped body 608, the mating features on the first ramped body 606may engage the mating features on the first and/or second endplates 602,604, thereby pushing (e.g., wedging) the first and second endplates 602,604 apart. In other embodiments, as the threaded member 704 is rotatedin a second direction, the threaded member 704 may push the first rampedbody 606 away from the second ramped body 608. Those skilled in the artmay appreciate that the device 600 may be reversibly expandable.Accordingly, some embodiments can include reducing the height of thedevice 600, for example, by bringing the first and second endplates 602,604 together.

In some embodiments, the device 600 can include a locking memberconfigured to lock the device 600 in a desired configuration (e.g., at adesired height). In other embodiments, after the device 600 is expanded,bone growth material may be introduced into the cavity 692 through achannel 691, as illustrated in FIG. 12F. The channel 691 may passthrough the first and/or second endplates 602, 604 from the outersurface 614, 638 to the cavity 692. In some embodiments, the channel 691may be located on the second side 620, 636 of the first and/or secondendplates 602, 604. Advantageously, the channel 691 may be positioned ata location (e.g., on the second side 620 and/or 636) configured toenable direct access by a surgeon in situ. In embodiments that includemovable extension portions 648, 660, methods herein can also include thestep of adjusting a position of one or both extension portions 648, 660relative to at least one of the body portions of the first and secondendplates 602, 604. In some embodiments, this step may be accomplishedby translating (e.g., sliding) one or both extension portions 648, 660along the respective body portions of the first and second endplates602, 604. For example, this step can include sliding a tongue member ofat least one of the first and second extension portions 648, 660 withina groove member of at least one of the respective body portions of thefirst and/or second endplates 602, 604. In other embodiments, the firstand/or second extension portions 648, 660 may be pivoted and/orarticulated relative to the respective body portions of the first and/orsecond endplates 602, 604. Some embodiments can also include locking theposition of at least one of the first and second extension portions 648,660 relative to the respective body portions of the first and/or secondendplates 602, 604.

Methods herein can also include the step of inserting fastener 651 intobore 650 and/or inserting fastener 663 into bore 662. This step caninclude inserting fastener 651 along an axis (e.g., axis 652) that isconfigured to intersect the longitudinal axis 626 and/or the vertical,longitudinal plane 658. This step can also include inserting fastener663 along an axis (e.g., axis 668) that is configured to intersect thelongitudinal axis 670 and/or the vertical, longitudinal plane 658. Insome embodiments, this step can include inserting fastener 651 and/orfastener 663 along an anterolateral and/or oblique trajectory. In otherembodiments, this step can include inserting fastener 651 into asuperior vertebra and inserting fastener 663 into an inferior vertebra.As described herein, those skilled in the art may appreciate that thistrajectory may advantageously avoid certain anatomical structures, suchas the psoas major, lumbar plexus, and/or iliac crest. Accordingly, insome embodiments, device 600 may be inserted laterally between lumbarvertebrae and subsequently coupled to the vertebrae with minimalinterference. After the fasteners 651 and/or 663 have been inserted,they may be secured by retention member 656 and/or 666. The retentionmembers 656, 666 may be disposed within the receptacles 654, 664. Theretention members 656, 666 may be configured to rotate until a portionof the retention members 656, 666 overlaps the bore 650, 662 andprevents the fasteners 651, 663 from backing out. Those skilled in theart may appreciate that in some embodiments, the fasteners 651, 663 maybe inserted prior to expansion of the device 600.

Turning now to FIGS. 13A-E, an alternative embodiment of a vertebralfusion device is illustrated. Unless otherwise described herein,vertebral fusion device 800 can include some or all of the features ofthe vertebral fusion devices described in U.S. patent application Ser.No. 14/449,428, entitled “VARIABLE LORDOSIS SPACER AND RELATED METHODSOF USE,” filed Aug. 1, 2014, U.S. Patent Publication No. 2014/0163683,entitled “EXPANDABLE VERTEBRAL IMPLANT,” published Jun. 12, 2014, andU.S. Patent Publication No. 2013/0023993, entitled “EXPANDABLE FUSIONDEVICE AND METHOD OF INSTALLATION THEREOF,” published Jan. 23, 2013.Vertebral fusion device 800 can include a first (e.g., upper and/orsuperior) endplate 802, a second (e.g., lower and/or inferior) endplate804, a first engagement, angled or ramped body 806, and a secondengagement, angled surface or ramped body 808. As illustrated in FIG.13D, the device 800 can also include a first side 801 and a second side803. As described further herein, vertebral fusion device 800 caninclude an adjustable height and/or lordotic angle. In some embodiments,one or both of the first and second sides 801, 803 may be configured topivotably expand about a pivot point P. The vertebral fusion device 800may be wedge-shaped along a latitudinal axis, such as seen from thefront view shown in FIG. 13D. For example, the device 800 may have aheight that increases from the first side 801 to the second side 803. Insome embodiments, the first and/or second ramped bodies 806, 808 may bewedge-shaped.

As illustrated in FIG. 13A, first endplate 802 can include a bodyportion that can include a first (e.g., leading and/or distal) end 810,a second (e.g., trailing and/or proximal) end 812, a first (e.g.,posterior) side 818, and a second (e.g., anterior) side 820. The firstendplate 802 can extend from the first side 801 to the second side 803of the device 800. The body portion of the first endplate 802 can alsoinclude an outer surface 814, an inner surface 816, an upper surface822, and a lower surface 828. The upper surface 822 can include aplurality of protrusions (e.g., bumps, teeth, and/or peaks) configuredto engage a vertebral body. The upper surface 822 can be generallyplanar, concave, and/or convex. As described further herein, the firstendplate 802 can include one or more mating features. In someembodiments, the mating feature(s) may be located on the inner surface816. The first side 818 may include at least one mating feature 823, andthe second side 820 may include at least one mating feature 824. In yetother embodiments, the first and/or second sides 818, 820 can eachinclude a mating feature at the first end 810, a mating feature at anintermediate portion, and/or a mating feature at the second end 812.

As illustrated in FIG. 13A, the first endplate 802 can also include afirst extension portion 848. The first extension portion 848 can extendfrom the second end 812 of the body portion of the first endplate 802.The first extension portion 848 can have a height that is greater than aheight of the body portion of the first endplate 802. For example, thefirst extension portion 848 may extend beyond the upper surface 822. Insome embodiments, the first extension portion 848 may be coupled (e.g.,attached, joined, and/or connected) to the body portion of the firstendplate 802. In some embodiments, the first extension portion 848 maybe moveably (e.g., articulably and/or jointedly) coupled to the bodyportion of the first endplate 802, for example, as described herein withrespect to vertebral fusion device 50. For example, the body portion ofthe first endplate 802 and the extension portion 848 may together form adovetail joint. In some embodiments, the first extension portion 848 andthe body portion of the first endplate 802 may each include a differentmaterial (e.g., a metal and/or a polymer). In other embodiments, thefirst extension portion 848 and the body portion of the first endplate802 may form a unitary body. The first extension portion 848 can includea bore 850 passing therethrough. The bore 850 can be configured toreceive a fastener therein. The first extension portion 848 can alsoinclude a receptacle 854. The receptacle 854 may at least partiallyoverlap the bore 850. The receptacle 854 may be configured to receive aretention member 856 therein.

As illustrated in FIG. 13B, the bore 850 can include an axis 852. Insome embodiments, axis 852 may be generally parallel to a longitudinalaxis (e.g., midline) and/or a vertical, longitudinal plane 858 of theassembled device 800. In other embodiments, axis 852 may be skewedrelative to the vertical, longitudinal plane 858. In yet otherembodiments, axis 852 may be configured to intersect the vertical,longitudinal plane 858. In some embodiments, the axis 852, bore 850,and/or first extension portion 848 may be horizontally offset from thelongitudinal midline and/or vertical, longitudinal plane 858. In someembodiments, the axis 852, bore 850, and/or first extension portion 848may be horizontally offset towards the second side 820. In otherembodiments, the axis 852, bore 850, and/or first extension portion 848may be horizontally offset towards the first side 818. In someembodiments, the axis 852 can intersect the plane 858 by an angle in therange of from about 0° to about 90°. In other embodiments, the axis 852can intersect the plane 858 by an angle in the range of from about 5° toabout 45°. In yet other embodiments, the axis 852 can intersect theplane 858 by an angle in the range of from about 20° to about 30°.

Second endplate 804 can include some or all of the same features as thefirst endplate 802. In some embodiments, the first and second endplates802, 804 may be symmetrical with respect to each other. As illustratedin FIG. 12A, second endplate 804 can include a body portion that caninclude a first (e.g., leading and/or distal) end 830, a second (e.g.,trailing and/or proximal) end 832, a first (e.g., posterior) side 834,and a second (e.g., anterior) side 836. The second endplate 804 canextend from the first side 801 to the second side 803 of the device 800.As illustrated in FIG. 13A, the body portion of the second endplate 804can also include an outer surface 838, an inner surface 840 (illustratedin FIG. 13D), an upper surface 842, and a lower surface 844. The lowersurface 844 can include a plurality of protrusions (e.g., bumps, teeth,and/or peaks) configured to engage a vertebral body. The lower surface844 can be generally planar, concave, and/or convex. As describedfurther herein, the second endplate 804 can include one or more matingfeatures. In some embodiments, the mating feature(s) may be located onthe inner surface 840. The first side 834 may include at least onemating feature 845, and the second side 820 may include at least onemating feature 846. In yet other embodiments, the first and/or secondsides 834, 836 can each include a mating feature at the first end 830, amating feature at an intermediate portion, and/or a mating feature atthe second end 832.

As illustrated in FIG. 13A, the second endplate 804 can also include asecond extension portion 860. The second extension portion 860 canextend from the second end 832 of the body portion of the secondendplate 804. The second extension portion 860 can have a height that isgreater than a height of the body portion of the second endplate 804.For example, the second extension portion 860 may extend beyond thelower surface 844. In some embodiments, the second extension portion 860may be coupled (e.g., attached, joined, and/or connected) to the bodyportion of the second endplate 804. In some embodiments, the secondextension portion 860 may be articulably and/or jointedly coupled to thebody portion of the second endplate 804, for example, as describedherein with respect to vertebral fusion device 50. For example, the bodyportion of the second endplate 804 and the second extension portion 860may together form a dovetail joint. In some embodiments, the secondextension portion 860 and the body portion of the second endplate 804may each include a different material (e.g., a metal and/or a polymer).In other embodiments, the second extension portion 860 and the bodyportion of the second endplate 804 may form a unitary body. The secondextension portion 860 can include a bore 862 passing therethrough. Thebore 862 can be configured to receive a fastener therein. The secondextension portion 860 can also include a receptacle 864. The receptacle864 may at least partially overlap the bore 862. The receptacle 864 maybe configured to receive a retention member 866 therein.

As illustrated in FIG. 13B, the bore 862 can include an axis 868. Insome embodiments, axis 868 may be generally parallel to a longitudinalaxis (e.g., midline) and/or the vertical, longitudinal plane 858. Inother embodiments, axis 868 may be skewed relative to the vertical,longitudinal plane 858. In yet other embodiments, axis 868 may beconfigured to intersect the vertical, longitudinal plane 858. In someembodiments, the axis 868, bore 862, and/or second extension portion 860may be horizontally offset from the longitudinal midline and/orvertical, longitudinal plane 858. In some embodiments, the axis 868,bore 862, and/or second extension portion 860 may be horizontally offsettowards the second side 836. In other embodiments, the axis 868, bore862, and/or second extension portion 860 may be horizontally offsettowards the first side 834. In some embodiments, the axis 868 canintersect the plane 858 by an angle in the range of from about 0° toabout 90°. In other embodiments, the axis 868 can intersect the plane858 by an angle in the range of from about 5° to about 45°. In yet otherembodiments, the axis 868 can intersect the plane 858 by an angle in therange of from about 20° to about 30°.

Mating feature 823 may be generally similar to mating feature 824,except that mating feature 824 may have different (e.g., larger)dimensions than mating feature 823. In some embodiments, mating features823, 824 of the first endplate 802 may be inclined (e.g., may extendfrom lower surface 828 towards upper surface 822) along longitudinalaxis 826 (illustrated in FIG. 13C) in a direction from the second end812 towards the first end 810. In some embodiments, mating features 823,824 may be angled, e.g., towards the first end 810. In otherembodiments, mating features 823, 824 may be inclined along thelongitudinal axis 826 in a direction from the first end 810 towards thesecond end 812. Mating feature 845 may be generally similar to matingfeature 846, except that mating feature 846 may have different (e.g.,larger) dimensions than mating feature 845. In some embodiments, matingfeatures 845, 846 of the second endplate 804 may be declined (e.g., mayextend from upper surface 842 towards lower surface 844) alonglongitudinal axis 826 in a direction from the second end 832 towards thefirst end 830. In some embodiments, mating features 845, 846 may beangled, e.g., towards the first end 830. In other embodiments, matingfeatures 845, 846 may be declined along the longitudinal axis 826 fromthe first end 830 towards the second end 832. Those skilled in the artmay appreciate that mating features 823, 824 of the first endplate 802may be symmetrical to (e.g., mirror images of) mating features 845, 846of the second endplate 804.

As described further herein, the first and/or second endplates 802, 804may be configured to engage (e.g., mate with) the first ramped body 806.As illustrated in FIG. 13A, the first ramped body 806 can include afirst (e.g., leading and/or distal) end 872, a second (e.g., trailingand/or proximal) end 874, a first (e.g., posterior) side portion 876,and a second (e.g., anterior) side portion 878. The first ramped body806 can also include a third (e.g., superior) end 880 and a fourth(e.g., inferior) end 882. The first ramped body 806 may extend from thefirst side 801 to the second side 803 of the device 800. The firstramped body 806 can include a plurality of mating features configured toengage the mating features on the first and/or second endplates 802,804. As illustrated in FIGS. 13A and 13E, the third end 880 can includeone or more mating features 883 on the first side 876 and one or moremating features 884 on the second side 878. The fourth end 882 caninclude one or more mating features 885 on the first side 876 and one ormore mating features 886 on the second side 878. Those skilled in theart may appreciate that mating features 884, 886 may extend in generallyopposite vertical directions. Additionally, mating features 883, 885 mayextend in generally opposite vertical directions. In some embodiments,the first side portion 876 can include at least two mating elements 883and at least two mating elements 885. In other embodiments, the secondside portion 878 can include at least two mating elements 884 and atleast two mating elements 886. In some embodiments, the first end 872 ofthe first ramped body 806 can include mating features 883, 884, 885, and886.

Each of the mating features of the first ramped body 806 may beconfigured (e.g., shaped) to mate with a corresponding mating feature onthe first and/or second endplates 802, 804. The mating features 883, 884may be configured to engage the mating features 823, 824 of the firstendplate 802. The mating features 885, 886 may be configured to engagethe mating features 845, 846 of the second endplate 804. Mating features884, 886 may have substantially similar inclinations, when in anassembled configuration, as their corresponding mating features 824,846. In some embodiments, each mating feature 884 is inclined towardsthe first end 872 of the first ramped body 806, and each mating feature886 is declined towards the first end 872 of the first ramped body 806.In other embodiments, mating feature 884 and mating feature 886 maydiverge from each other along a longitudinal axis from a positionrelatively adjacent to the second end 874 to a position relativelyadjacent to the first end 872. In yet other embodiments, the matingfeatures 884, 886 may be angled, e.g., towards the first end 872. Instill other embodiments, one or more mating features 884 may be inclinedtowards the second end 874 of the first ramped body 806 and/or one ormore mating features 886 may be declined towards the second end 874 ofthe first ramped body 806. In some embodiments, one or more matingfeatures 884, 886 can include a protrusion (e.g., a tongue, rail, and/orshoulder). In some embodiments, the protrusion can be integrally formedwith the body of the first ramped body 806, or can be a separatecomponent. For example, in some embodiments, a series of external pinscan create a protrusion in the form of a rail. In other embodiments, oneor more mating features 884, 886 can include a recess (e.g., a groove,track, and/or channel). In some embodiments, for example, as illustratedin FIGS. 13A and 13E, the mating features 884, 886 can alternatelongitudinally along the second side 878. Each mating feature 884 on thefirst ramped body 806 can be generally the same. Each mating feature 886may be generally the same. In some embodiments, at least one matingfeature 884 and/or 886 may include different properties as compared tothe other mating features 884, 886. Mating feature(s) 883 may be similarto mating feature(s) 884, except that mating feature(s) 884 may havedifferent (e.g., larger) dimensions than mating feature(s) 883. Matingfeature(s) 885 may be similar to mating feature(s) 886, except thatmating feature(s) 886 may have different (e.g., larger) dimensions thanmating feature(s) 885. In some embodiments, the mating features 883, 885can alternate longitudinally along the first side 876. In otherembodiments, the mating features 883, 884 can alternate transverselyalong the third end 880 of the first and/or second sides 876, 878. Inyet other embodiments, the mating features 885, 886 can alternatetransversely along the fourth end 882 of the first and/or second sides876, 878. In some embodiments, each mating feature 883 may be generallythe same. In other embodiments, each mating feature 885 may be generallythe same. In yet other embodiments, at least one of the mating features883, 885 may include different properties as compared to the othermating features 883, 885.

The mating features 823, 824 on the first endplate 802 may be configuredto form a slidable joint with a corresponding mating feature 883, 884 onthe first ramped body 806. The mating features 845, 846 on the secondendplate 804 may be configured to form a slidable joint with acorresponding mating feature 885, 886 on the first ramped body 806.Accordingly, the first ramped body 806 may be configured to slideablyengage the first and/or second endplates 802, 804. The slideable jointmay advantageously enable the vertebral fusion device 800 to transitionreversibly between expanded and contracted configurations. The slidablejoint may include, for example, a tabled splice joint, a dovetail joint,a tongue and groove joint, or another suitable joint. In someembodiments, one or more mating features on the first and/or secondendplates 802, 804 can include a recess (e.g., a groove, track, and/orchannel), and one or more mating features on the first ramped body 806can include a protrusion (e.g., a tongue, rail, and/or shoulder)configured to slide within the groove. In other embodiments, one or moremating features on the first and/or second endplates 802, 804 caninclude a protrusion and one or more mating features on the first rampedbody 806 can include a recess.

The mating features 883, 884, 885, 886 on the first ramped body 806 maybe curved in order to impart curvature to the first and second sides801, 803 of the device 800. Advantageously, one or more of thecurvatures of the mating features 883, 884, 885, 886 can be in the formof a helix, which results in the first endplate 802 and the secondendplate 804 moving not just parallel away from one another, but also atan angle (as shown in FIG. 13D). The mating features of the first rampedbody 806 may have a radius of curvature about the pivot point P.Furthermore, as the mating features of the first ramped body 806 may becomplementary to corresponding mating features on the first and secondendplates 802, 804, the mating features on the first and/or secondendplates 802, 804 may also be curved (e.g., may include a radius ofcurvature about the pivot point P).

As illustrated in FIG. 13A, the second end 874 of the first ramped body806 can include a first threaded bore 888 passing longitudinallytherethrough. The first threaded bore 888 may be configured to receive(e.g., threadably engage) a threaded member 904 of an actuator 902. Asillustrated in FIG. 13A, the threaded member 904 of the actuator 902 caninclude a proximal end having a tool-engaging recess 910. The actuator902 can also include a washer 906 and/or one or more snap rings 908,909. The second end 874 of the first ramped body 806 can also include asecond bore 890 passing longitudinally therethrough. In someembodiments, the second bore 890 may be threaded. The second bore 890may be configured to engage an inserter. In other embodiments, thesecond bore 890 can advantageously be configured for use as an accessport to enable bone growth material to be delivered into a cavity of thedevice 800. The second bore 890 may be laterally displaced from thefirst threaded bore 888. In some embodiments, the first threaded bore888 may be located adjacent to the second side 878 of the first rampedbody 806 and the second bore 890 may be located adjacent to the firstside 876, or vice versa. In other embodiments, the first threaded bore888 may be anteriorly offset relative to the second bore 890, or viceversa. In some embodiments, the second bore 890 can be located adjacentto the second side 878 and/or anteriorly offset relative to the firstthreaded bore 888. In these embodiments, the device 800 may beadvantageously configured to engage an inserter at an angle offset fromthe plane 858, thereby enabling a user to position the device 800 in adirect lateral orientation, e.g., in a patient's lumbar spine, whilereducing interaction with the psoas muscle.

The first threaded bore 888 and/or the second bore 890 can include anaxis that is horizontally offset from the vertical, longitudinal plane858. In some embodiments, the axis (e.g., of the first threaded bore 888and/or the second bore 890) can be horizontally offset towards thesecond side 878. In some embodiments, the axis (e.g., of the firstthreaded bore 888 and/or the second bore 890) can be parallel or skewedrelative to the vertical, longitudinal plane 858. In other embodiments,the axis of the first threaded bore 888 and/or the second bore 890 canintersect the plane 858 to form an angle. In some embodiments, the anglecan be in the range of from about 0° to about 90°. In other embodiments,the angle can be in the range of from about 5° to about 45°. In yetother embodiments, the angle can be in the range of from about 20° toabout 30°.

When in an assembled configuration, the second ramped body 808 can bedisposed adjacent to the first ramped body 806. The second ramped body808 can extend from the first side 801 to the second side 803 of thedevice 800. Second ramped body 808 can include one or more matingfeatures configured to engage corresponding mating features 823, 824,845, 846 on the first and/or second endplates 802, 804. The matingfeatures on the second ramped body 808 can include some or all of thesame features as the mating features 883, 884, 885, 886 of the firstramped body 806. For example, the mating features on the second rampedbody 808 can be curved in order to impart curvature to the first andsecond sides 801, 803 of the device 800. As illustrated in FIG. 13A, thesecond ramped body 808 can include a first bore 894. The first bore 894can be configured to be coaxial with the first threaded bore 888 of thefirst ramped body 806 when in an assembled configuration. The first bore894 may be configured to receive the head portion of the actuator 902therein. In use, the head portion may be configured to rotate within thefirst bore 894. The second ramped body 808 can also include a secondbore 896. The first and/or second bores 894, 896 may be threaded. Insome embodiments, the second bore 896 can be configured to engage aninserter. The second bore 896 can be configured to be coaxial with thesecond bore 890 of the first ramped body 806 when in an assembledconfiguration. The second bore 896 can be laterally displaced from thefirst bore 894. In some embodiments, the first bore 894 may be locatedadjacent to a second side 898 of the second ramped body 808 and thesecond bore 896 may be located adjacent to a first side 897, asillustrated in FIG. 13A. In other embodiments, the first bore 894 may belocated adjacent to the first side 897 and the second bore 896 may belocated adjacent to the second side 898. In other embodiments, the firstbore 894 may be anteriorly offset relative to the second bore 896, orvice versa. In some embodiments, the second bore 896 can be locatedadjacent to the second side 898 and/or anteriorly offset relative to thefirst bore 894. In these embodiments, the device 800 may beadvantageously configured to engage an inserter at an angle offset fromthe plane 858, thereby enabling a user to position the device 800 in adirect lateral orientation, e.g., in a patient's lumbar spine, whilereducing interaction with the psoas muscle.

The first threaded bore 894 and/or the second bore 896 can include anaxis that is horizontally offset from the vertical, longitudinal plane858. In some embodiments, the axis of the first bore 894 and/or thesecond bore 896 can be horizontally offset towards the second side 898.In some embodiments, the axis of the first bore 894 and/or the secondbore 896 can be parallel and/or skewed relative to the plane 858. Inother embodiments, the axis of the first bore 894 and/or the second bore896 can intersect the plane 858 to form an angle. In some embodiments,the angle can be in the range of from about 0° to about 90°. In otherembodiments, the angle can be in the range of from about 0° to about45°. In yet other embodiments, the angle can be in the range of fromabout 20° to about 30°.

The vertebral fusion device 800 can advantageously include an adjustableheight and/or lordotic angle. In some embodiments, the device 800 may beexpandable. The vertebral fusion device 800 may advantageously beconfigured to reversibly transition between a collapsed configurationand an expanded configuration. In the collapsed configuration, forexample, as illustrated in FIGS. 13B-C, the vertebral fusion device 800can include a first height (e.g., as measured from the upper surface 822of the first endplate 802 to the lower surface 844 of the secondendplate 804). In some embodiments, the device 800 (e.g., first andsecond endplates 802, 804) may define a first angle when in thecollapsed configuration. In other embodiments, the first and secondendplates 802, 804 may be generally parallel when in the collapsedconfiguration. In some embodiments, the first endplate 802 and thesecond endplate 804 can begin at an angle, and can be expanded to agreater angle.

In the expanded configuration, for example, as illustrated in FIGS.13D-E, the vertebral fusion device 800 can include a second height thatis greater than the first height. In some embodiments, the second heightcan be from about 25% to about 200% greater than the first height. Inother embodiments, the second height can be from about 100% to about150% greater than the first height. In some embodiments, the firstheight can be in the range of from about 5 mm to about 10 mm, and/or thesecond height can be in the range of from about 15 mm to about 20 mm. Insome embodiments, the change in height can be caused by movement of thefirst and second endplates 802, 804 towards and/or away from each other.In these embodiments, the first and second endplates 802, 804 can beseparated by a first distance when in the collapsed configuration and asecond distance when in the expanded configuration, wherein the seconddistance is greater than the first distance. Those skilled in the artmay appreciate that, in use, the height of the vertebral fusion device800 can be adjusted to accommodate an individual patient's anatomy.Additionally, the device 800 may be inserted into an intervertebralspace in the collapsed configuration, which may entail less trauma tosurrounding tissue due to its smaller size.

In other embodiments, at least one of the first and second endplates802, 804 may be configured to pivot about pivot point P, illustrated inFIG. 13D. In these embodiments, the change in height can be caused bypivoting the first and/or second endplates 802, 804 about pivot point P.In these embodiments, the first and second endplates 802, 804 beoriented at a first angle when in the collapsed configuration. The firstand/or second endplates 802, 804 can pivot apart about the pivot point Pto expand the device 800 and orient the first and second endplates 802,804 at a second angle. In some embodiments, the first (e.g., collapsed)angle can be in the range of from about 5° to about 20°. For example,the first angle may be about 10.4°. In other embodiments, the second(e.g., expanded) angle can be in the range of from about 10° to about40°. For example, the second angle may be about 22.5°. Those skilled inthe art may appreciate that in some embodiments, the device 800 can beexpanded by both the linear and pivotal movement of the first and/orsecond endplates 802, 804 away from each other.

Embodiments herein are also directed to methods of installing thevertebral fusion device 800. Methods can include providing the device800 in the collapsed configuration, for example, as illustrated in FIGS.13B-C. In some embodiments, this step can include providing (e.g.,inserting and/or positioning) the device 800 between two adjacentvertebrae (e.g., between the L4 and L5 vertebrae). In some embodiments,the device 800 can be inserted using an inserter, such as a straightinserter or an angled inserter. In these embodiments, the methods ofinstallation can include coupling the inserter with the device 800, forexample, threading a threaded member of the inserter into the secondbore 890, 896 of the first and/or second ramped bodies 806, 808. In someembodiments, the device 800 may be inserted along a lateral approach,for example, when a straight inserter is used. In other embodiments, thedevice 800 can be inserted along an anterolateral and/or obliqueapproach, for example, when an angled inserter is used. In theseembodiments, the device 800 can be subsequently pivoted into a lateralorientation while in the intervertebral space. In some embodiments, thedevice 800 may be inserted using minimally invasive methods. In someembodiments, the intervertebral space may be prepared beforehand, forexample, by performing a discectomy to remove some or all of theintervertebral disc.

Methods herein can also include expanding the device 800, for example,by transitioning the device 800 from the collapsed configuration to theexpanded configuration. This step can include pivotably expanding atleast one of the first and second sides 801, 803 of the device 800. Insome embodiments, the first and second sides 801, 803 may be pivotablyexpanded at a same angular rate of change about the pivot point P. Toexpand the device 800, at least one of the first and second rampedbodies 806, 808 may be translated relative to at least one of the firstand second endplates 802, 804. For example, the second ramped body 808may be moved (e.g., translated) towards the first ramped body 806, orvice versa. The mating features of the first and/or second ramped bodies806, 808 may engage the mating features of the first and/or secondendplates 802, 804. As the first and second ramped bodies 806, 808translate towards each other, the respective mating features of thefirst and second ramped bodies 806, 808 may push against correspondingmating features on the first and second endplates 802, 804, therebypushing (e.g., pivoting) the first and second endplates 802, 804 apartand increasing the height and/or angle of the device 800. The device 800can be expanded until it defines a second angle with respect to thepivot point P, wherein the second angle is greater than the first angle.

In some embodiments, the step of expanding the device 800 can includeactuating the actuator 902. This step can include inserting the threadedmember 904 into the first bore 894 of the second ramped body 808 and thefirst threaded bore 888 of the first ramped body 806. This step can alsoinclude applying a rotational force to the threaded member 904 tothreadably engage the first ramped body 806. The rotational force can beadded directly (e.g., manually) and/or indirectly (e.g., through adriver or other tool). In some embodiments, as the threaded member 904is rotated in a first direction, the threaded member 904 may pull thefirst ramped body 806 towards the second ramped body 808. As the firstramped body 806 moves towards the second ramped body 808, the matingfeatures on the first ramped body 806 may engage the mating features onthe first and/or second endplates 802, 804, thereby pushing (e.g.,wedging and/or pivoting) the first and second endplates 802, 804 apart.In other embodiments, as the threaded member 904 is rotated in a seconddirection, the threaded member 904 may push the first ramped body 806away from the second ramped body 808. Those skilled in the art mayappreciate that the device 800 may be reversibly expandable.Accordingly, some embodiments can include reducing the height and/orangle of the device 800, for example, by bringing the first and secondendplates 802, 804 together.

In some embodiments, the device 800 can include a locking memberconfigured to lock the device 800 in a desired configuration (e.g., at adesired height and/or angle). In these embodiments, the methods canfurther include locking the device 800 in the expanded configuration. Inother embodiments, after the device 800 is expanded, bone growthmaterial may be introduced into a cavity within the device 800 throughthe second bores 890 and/or 896 of the first and second ramped bodies806, 808. In some embodiments, the first and/or second endplate 802, 804can include a channel passing from an outer surface to an inner surfaceand configured to receive bone graft material therethrough. Inembodiments that include movable extension portions 848, 860, methodsherein can also include the step of adjusting a position of one or bothextension portions 848, 860 relative to at least one of the bodyportions of the first and second endplates 802, 804. In someembodiments, this step may be accomplished by translating (e.g.,sliding) one or both extension portions 848, 860 along the respectivebody portions of the first and second endplates 802, 804. For example,this step can include sliding a tongue member of at least one of thefirst and second extension portions 848, 860 within a groove member ofat least one of the respective body portions of the first and/or secondendplates 802, 804. In other embodiments, the first and/or secondextension portions 848, 860 may be pivoted and/or articulated relativeto the respective body portions of the first and/or second endplates802, 804. Some embodiments can also include locking the position of atleast one of the first and second extension portions 848, 860 relativeto the respective body portions of the first and/or second endplates802, 804.

Methods herein can also include the step of inserting a first fastenerinto bore 850 along first axis 852 and/or a second fastener into bore862 along second axis 868. In some embodiments, this step can includeinserting the fastener(s) along an axis that is parallel and/or skewedrelative to the vertical, longitudinal plane 858. In other embodiments,this step can include inserting the fastener(s) along an axis that isconfigured to intersect the vertical, longitudinal plane 858. In someembodiments, this step can include inserting the fastener(s) along ananterolateral and/or oblique trajectory. In other embodiments, this stepcan include inserting the first fastener into a superior vertebra andinserting the second fastener into an inferior vertebra. As describedherein, those skilled in the art may appreciate that this trajectory mayadvantageously avoid certain anatomical structures, such as the psoasmajor, lumbar plexus, and/or iliac crest. Accordingly, in someembodiments, device 800 may be inserted laterally between lumbarvertebrae and subsequently coupled to the vertebrae with minimalinterference. After the fasteners have been inserted, they may besecured by retention member 856 and/or 866. The retention members 856,866 may be disposed within the receptacles 854, 864. The retentionmembers 856, 866 may be configured to rotate until a portion of theretention members 856, 866 overlaps the bore 850, 862 and prevents thefasteners from backing out. Those skilled in the art may appreciate thatin some embodiments, the first and/or second fasteners may be insertedprior to expansion of the device 800.

The devices described herein can be used in combination with variousother implants and tools used in spinal surgery. In some embodiments,the implants described herein can be accompanied with other stabilizingmembers, including plates, rods and pedicle screws. In addition, thedevices can be used with prosthetic devices or other fusion baseddevices.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are intendedto be included within the scope of the following claims. Althoughindividual embodiments are discussed herein, the invention covers allcombinations of all those embodiments.

1. A vertebral fusion device, comprising: a first endplate adapted tocontact a first vertebral body; a second endplate adapted to contact asecond vertebral body adjacent to the first vertebral body; a matingelement coupled to the first and second endplates and having a curvedguide; an articulating support having a central axis and coupled to thecurved guide for articulating movement along the curved guide, thearticulating support having an actuator adapted to expand the firstendplate relative to the second endplate; a fixation plate coupled tothe articulating support and adapted to be circumferentially rotatableabout the central axis of the articulating support, the fixation platehaving a bore for receiving a fastener for insertion into a vertebralbody.
 2. The vertebral fusion device of claim 1, further comprising apost attached to the articulating support along the central axis and thefixation plate is rotatably attached to the post.
 3. The vertebralfusion device of claim 2, wherein the fixation plate is translationallyadjustable along the post.
 4. The vertebral fusion device of claim 3,further comprising a nut threadably attached to the post to fix thefixation plate to the articulating support.
 5. The vertebral fusiondevice of claim 1, further comprising: an externally threaded postattached to the articulating support and through which the fixationplate is attached; a threaded nut threaded to the external threading ofthe post and adapted to adjust the position of the fixation plate alongthe central axis.
 6. The vertebral fusion device of claim 1, wherein:the mating element has an external curved surface; the articulatingsupport has a complementary curved inner surface and the articulatingsupport articulates along the external curved surface.
 7. The vertebralfusion device of claim 1, further comprising: a frame disposed betweenthe first and second endplates and coupled to the mating element,wherein the articulating support includes a rotatable nut coupled to theframe such that as the nut rotates the frame translates which causes thefirst and second endplates to expand or contract.
 8. The vertebralfusion device of claim 7, further comprising a link coupled to the frameand threadingly coupled to the nut.
 9. The vertebral fusion device ofclaim 1, wherein the fixation member has a plurality of bores forreceiving a fastener.
 10. The vertebral fusion device of claim 9,further comprising a post attached to the articulating support along thecentral axis and the post receives the fixation plate through thecentral opening.
 11. A vertebral fusion device, comprising: anexpandable spacer including: first and second endplates having rampedsurfaces; a frame disposed between the first and second endplates andhaving ramped surfaces that mesh with the ramped surfaces of the firstand second endplates; a mating element coupled to the first and secondendplates and the frame, the mating element having a curved guide; anarticulating support having a central axis and having a complementaryguide coupled to the curved guide for articulating movement along thecurved guide, the articulating support having an actuator adapted totranslate the frame relative to the first and second endplates forexpansion of the first end plate relative to the second plate; afixation plate coupled to the articulating support and extendinglaterally from the central axis, the fixation plate adapted to becircumferentially rotatable about the central axis of the articulatingsupport, the fixation plate having a bore for receiving a fastener forinsertion into a vertebral body.
 12. The vertebral fusion device ofclaim 1, further comprising a threaded post attached to the articulatingsupport along the central axis and the fixation plate is rotatablyattached to the post.
 13. The vertebral fusion device of claim 12,wherein the fixation plate is translationally adjustable along thecentral axis of the articulating support.
 14. The vertebral fusiondevice of claim 3, further comprising a nut threadably attached to thepost adapted to secure the fixation plate to the articulating support.15. The vertebral fusion device of claim 11, further comprising: anexternally threaded post attached to the articulating support andthrough which the fixation plate is attached; a threaded nut threaded tothe external threading of the post and adapted to adjust the position ofthe fixation plate along the central axis.
 16. The vertebral fusiondevice of claim 11, wherein: the mating element has an external curvedsurface; the articulating support has a complementary curved innersurface and the articulating support articulates along the externalcurved surface.
 17. The vertebral fusion device of claim 11, wherein thearticulating support includes a rotatable nut coupled to the frame suchthat as the nut rotates the frame translates which causes the first andsecond endplates to expand or contract.
 18. The vertebral fusion deviceof claim 17, further comprising a link coupled to the frame andthreadingly coupled to the nut.
 19. The vertebral fusion device of claim11, wherein the fixation member has a plurality of bores for receiving afastener.
 20. The vertebral fusion device of claim 19, furthercomprising a post attached to the articulating support along the centralaxis and the post receives the fixation plate through the centralopening.